The reference to packages ending in -archive-keyring appears to be
outdated. The quick survey below shows that such keyrings nowadays end
up in /etc/apt/trusted.gpg.d/.

That folder is covered by the tag package-installs-apt-keyring. The
obsolete reference in this tag is herewith removed.

Thanks to Ferenc Wágner for bringing the matter to our attention!

$ find /mirror/debian/pool/ -type f -name '*-archive-keyring*'
/mirror/debian/pool/main/n/neurodebian/neurodebian-archive-keyring_0.41.0_all.deb
/mirror/debian/pool/main/l/leap-archive-keyring/leap-archive-keyring_2017.11.24+nmu1_all.deb
/mirror/debian/pool/main/u/ubuntu-keyring/ubuntu-archive-keyring_2020.06.17.1-1_all.deb
/mirror/debian/pool/main/f/fasttrack-archive-keyring/fasttrack-archive-keyring_2020.12.19_all.deb
/mirror/debian/pool/main/p/pkg-mozilla-archive-keyring/pkg-mozilla-archive-keyring_1.2+nmu1_all.deb
/mirror/debian/pool/main/d/debian-ports-archive-keyring/debian-ports-archive-keyring_2020.02.02_all.deb
/mirror/debian/pool/main/d/debian-archive-keyring/debian-archive-keyring_2021.1.1_all.deb

$ dpkg-deb -c /mirror/debian/pool/main/n/neurodebian/neurodebian-archive-keyring_0.41.0_all.deb
drwxr-xr-x root/root         0 2021-02-15 19:04 ./
drwxr-xr-x root/root         0 2021-02-15 19:04 ./etc/
drwxr-xr-x root/root         0 2021-02-15 19:04 ./etc/apt/
drwxr-xr-x root/root         0 2021-02-15 19:04 ./etc/apt/trusted.gpg.d/
-rw-r--r-- root/root      1511 2021-02-15 19:04 ./etc/apt/trusted.gpg.d/neurodebian-archive-keyring.gpg
drwxr-xr-x root/root         0 2021-02-15 19:04 ./usr/
drwxr-xr-x root/root         0 2021-02-15 19:04 ./usr/share/
drwxr-xr-x root/root         0 2021-02-15 19:04 ./usr/share/doc/
drwxr-xr-x root/root         0 2021-02-15 19:04 ./usr/share/doc/neurodebian-archive-keyring/
-rw-r--r-- root/root      6809 2021-02-15 19:04 ./usr/share/doc/neurodebian-archive-keyring/changelog.gz
-rw-r--r-- root/root      3700 2021-02-15 19:04 ./usr/share/doc/neurodebian-archive-keyring/copyright

$ dpkg-deb -c /mirror/debian/pool/main/l/leap-archive-keyring/leap-archive-keyring_2017.11.24+nmu1_all.deb
drwxr-xr-x root/root         0 2021-01-03 04:42 ./
drwxr-xr-x root/root         0 2021-01-03 04:42 ./etc/
drwxr-xr-x root/root         0 2021-01-03 04:42 ./etc/apt/
drwxr-xr-x root/root         0 2021-01-03 04:42 ./etc/apt/trusted.gpg.d/
-rw-r--r-- root/root      2848 2017-11-07 13:13 ./etc/apt/trusted.gpg.d/leap-archive.gpg
-rw-r--r-- root/root      2869 2017-11-07 13:13 ./etc/apt/trusted.gpg.d/leap-experimental-archive.gpg
drwxr-xr-x root/root         0 2021-01-03 04:42 ./usr/
drwxr-xr-x root/root         0 2021-01-03 04:42 ./usr/share/
drwxr-xr-x root/root         0 2021-01-03 04:42 ./usr/share/doc/
drwxr-xr-x root/root         0 2021-01-03 04:42 ./usr/share/doc/leap-archive-keyring/
-rw-r--r-- root/root      1146 2021-01-03 04:42 ./usr/share/doc/leap-archive-keyring/changelog.gz
-rw-r--r-- root/root      1054 2016-11-18 06:47 ./usr/share/doc/leap-archive-keyring/copyright
drwxr-xr-x root/root         0 2021-01-03 04:42 ./usr/share/keyrings/
-rw-r--r-- root/root      2848 2017-11-07 13:13 ./usr/share/keyrings/leap-archive.gpg
-rw-r--r-- root/root      2869 2017-11-07 13:13 ./usr/share/keyrings/leap-experimental-archive.gpg

$ dpkg-deb -c /mirror/debian/pool/main/p/pkg-mozilla-archive-keyring/pkg-mozilla-archive-keyring_1.2+nmu1_all.deb
drwxr-xr-x root/root         0 2021-01-01 07:47 ./
drwxr-xr-x root/root         0 2021-01-01 07:47 ./etc/
drwxr-xr-x root/root         0 2021-01-01 07:47 ./etc/apt/
drwxr-xr-x root/root         0 2021-01-01 07:47 ./etc/apt/trusted.gpg.d/
-rw-r--r-- root/root      1853 2021-01-01 07:47 ./etc/apt/trusted.gpg.d/pkg-mozilla-archive-keyring.gpg
drwxr-xr-x root/root         0 2021-01-01 07:47 ./usr/
drwxr-xr-x root/root         0 2021-01-01 07:47 ./usr/share/
drwxr-xr-x root/root         0 2021-01-01 07:47 ./usr/share/doc/
drwxr-xr-x root/root         0 2021-01-01 07:47 ./usr/share/doc/pkg-mozilla-archive-keyring/
-rw-r--r-- root/root       574 2021-01-01 07:47 ./usr/share/doc/pkg-mozilla-archive-keyring/changelog.gz
-rw-r--r-- root/root       479 2018-05-27 17:11 ./usr/share/doc/pkg-mozilla-archive-keyring/copyright

$ dpkg-deb -c /mirror/debian/pool/main/d/debian-ports-archive-keyring/debian-ports-archive-keyring_2020.02.02_all.deb
drwxr-xr-x root/root         0 2021-02-02 10:12 ./
drwxr-xr-x root/root         0 2021-02-02 10:12 ./etc/
drwxr-xr-x root/root         0 2021-02-02 10:12 ./etc/apt/
drwxr-xr-x root/root         0 2021-02-02 10:12 ./etc/apt/trusted.gpg.d/
-rw-r--r-- root/root      1210 2021-02-02 10:12 ./etc/apt/trusted.gpg.d/debian-ports-archive-2021.gpg
-rw-r--r-- root/root      1210 2021-02-02 10:12 ./etc/apt/trusted.gpg.d/debian-ports-archive-2022.gpg
drwxr-xr-x root/root         0 2021-02-02 10:12 ./usr/
drwxr-xr-x root/root         0 2021-02-02 10:12 ./usr/share/
drwxr-xr-x root/root         0 2021-02-02 10:12 ./usr/share/doc/
drwxr-xr-x root/root         0 2021-02-02 10:12 ./usr/share/doc/debian-ports-archive-keyring/
-rw-r--r-- root/root       475 2016-01-24 14:59 ./usr/share/doc/debian-ports-archive-keyring/README
-rw-r--r-- root/root      1689 2021-02-02 10:12 ./usr/share/doc/debian-ports-archive-keyring/changelog.gz
-rw-r--r-- root/root      1007 2010-05-13 02:31 ./usr/share/doc/debian-ports-archive-keyring/copyright
drwxr-xr-x root/root         0 2021-02-02 10:12 ./usr/share/keyrings/
-rw-r--r-- root/root     23857 2021-02-02 10:12 ./usr/share/keyrings/debian-ports-archive-keyring-removed.gpg
-rw-r--r-- root/root      2420 2021-02-02 10:12 ./usr/share/keyrings/debian-ports-archive-keyring.gpg

$ dpkg-deb -c /mirror/debian/pool/main/d/debian-archive-keyring/debian-archive-keyring_2021.1.1_all.deb
drwxr-xr-x root/root         0 2021-02-25 09:38 ./
drwxr-xr-x root/root         0 2021-02-25 09:38 ./etc/
drwxr-xr-x root/root         0 2021-02-25 09:38 ./etc/apt/
drwxr-xr-x root/root         0 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/
-rw-r--r-- root/root      8700 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-bullseye-automatic.gpg
-rw-r--r-- root/root      8709 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-bullseye-security-automatic.gpg
-rw-r--r-- root/root      2453 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-bullseye-stable.gpg
-rw-r--r-- root/root      8132 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-buster-automatic.gpg
-rw-r--r-- root/root      8141 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-buster-security-automatic.gpg
-rw-r--r-- root/root      2332 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-buster-stable.gpg
-rw-r--r-- root/root      7443 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-stretch-automatic.gpg
-rw-r--r-- root/root      7452 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-stretch-security-automatic.gpg
-rw-r--r-- root/root      2263 2021-02-25 09:38 ./etc/apt/trusted.gpg.d/debian-archive-stretch-stable.gpg
drwxr-xr-x root/root         0 2021-02-25 09:38 ./usr/
drwxr-xr-x root/root         0 2021-02-25 09:38 ./usr/share/
drwxr-xr-x root/root         0 2021-02-25 09:38 ./usr/share/doc/
drwxr-xr-x root/root         0 2021-02-25 09:38 ./usr/share/doc/debian-archive-keyring/
-rw-r--r-- root/root      1091 2021-02-24 13:08 ./usr/share/doc/debian-archive-keyring/README
-rw-r--r-- root/root      3514 2021-02-25 09:38 ./usr/share/doc/debian-archive-keyring/changelog.gz
-rw-r--r-- root/root      1243 2021-02-05 08:05 ./usr/share/doc/debian-archive-keyring/copyright
drwxr-xr-x root/root         0 2021-02-25 09:38 ./usr/share/keyrings/
-rw-r--r-- root/root      8700 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-bullseye-automatic.gpg
-rw-r--r-- root/root      8709 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-bullseye-security-automatic.gpg
-rw-r--r-- root/root      2453 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-bullseye-stable.gpg
-rw-r--r-- root/root      8132 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-buster-automatic.gpg
-rw-r--r-- root/root      8141 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-buster-security-automatic.gpg
-rw-r--r-- root/root      2332 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-buster-stable.gpg
-rw-r--r-- root/root     55625 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-keyring.gpg
-rw-r--r-- root/root     36873 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-removed-keys.gpg
-rw-r--r-- root/root      7443 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-stretch-automatic.gpg
-rw-r--r-- root/root      7452 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-stretch-security-automatic.gpg
-rw-r--r-- root/root      2263 2021-02-25 09:38 ./usr/share/keyrings/debian-archive-stretch-stable.gpg