Hi! We still have https://salsa.debian.org/mariadb-team/mariadb-server/-/merge_requests/61 open to potentially change the defaults, but I am hesitant to diverge from upstream on this.
Seems https://salsa.debian.org/mariadb-team/mariadb-server/-/commit/02f6ba571e930493c51b92b8c23e2e7fadcedbe0 only changed the warning to a note, which hides it, but the actual issue or default didn't change. Upstream default is also still '10': expire-logs-days 10 https://salsa.debian.org/mariadb-team/mariadb-server/-/blob/833461bed4a4424c9c9ce77d876a0982c48e1a37/debian/tests/traces/mariadbd-verbose-help.expected#L2612