I have certain hosts behind a single IP and forward SSH to them on arbitrarily chosen ports.
Do I still get random logins on those ports?
Why yes I do.
Does putting SSH on a different port make any difference?
No it doesn't.
Putting SSH on a different port is either done for a specific reason, or you're just deluding yourself that you've somehow reduced your attack surface.
On the other 20+ boxen with ssh on port xxx22 the logs and f2b rules are much smaller - which means less hassle for the admin.
And on the boxen with services behind WG there is zero noise.
Naturally we're using keys only with all this. The reduced noise in the logs/rules/firewall are very handy.
[0] https://www.youtube.com/watch?v=xkrMsPiqG6M&feature=youtu.be...
Yes. The specific reason is "it makes log files less full of crap we have to sift through".