Hi! Note that MySQL 8.0 will be end-of-life in 2026, so not only will it be FTBFS during trixie, it will also be out of support. However, Debian only releases with MariaDB - the package mysql-8.0 is only in unstable and will never be promoted to testing/trixie.
As long as MariaDB is 2038 compatible we are all good. There is a separate effort to test and ensure it at https://salsa.debian.org/mariadb-team/mariadb-server/-/merge_requests/74
