I would expect --trust-model always to mean that every key in my keyring is "trusted". But the last line of gpg output seems to contradict that:
$ gpg --homedir g --trust-model always --verify test.msg.sig test.msg gpg: Signature made Fri 14 Mar 2025 02:00:18 PM EDT gpg: using EDDSA key 08E9FF71DEA7111BF836E4CE97D936B918D1B12A gpg: Good signature from "test key" [unknown] gpg: WARNING: Using untrusted key! $