This isn't for everyone and it will block old ssh libraries (libssh, go ssh, etc...), windows and others but if you only have OpenSSH 10+ and that's all you connect with then this method [1] has worked well for me. It gets botters to exclude my nodes that expose SSH on purpose
(such as public anonymous SFTP). If trying it out test from an out of band console first.
Edit: I should add, there will still be some syslog entries, but that can be filtered out using regex filters in rsyslog one so desired. Only do so once it is confirmed most of the brute forcing has stopped.
[1] - https://nochan.net/b/Internet-Crap/20260108-Confuse-Some-SSH...