If it has been removed, then why do we see this message in the current version of Debian? That makes no sense.
This is an automatic notification regarding your Bug report
which was filed against the apt package:
#1104186: /usr/bin/apt-key: Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
It has been closed by Julian Andres Klode <jak@jak-linux.org>.
Their explanation is attached below along with your original report.
If this explanation is unsatisfactory and you have not received a
better one in a separate message then please contact Julian Andres Klode <jak@jak-linux.org> by
replying to this email.
--
1104186: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1104186
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