This is fine, though. "Security through obscurity is not security" but moving your SSH port to something not 22 will utterly eliminate brute force attacks.
It's too much bother to go find it, and the bozos will just move on to the next machine with port 22 open.
Nuisance mitigations are part of security too! Fewer irrelevant notifications makes it more likely you’ll notice when something really is a problem.
It’s like how an adversary might launch a DDoS attack at the same time as they exploit a SQL injection vulnerability to exfiltrate credit card information. Filling up logs and alerts overwhelms the blue team and makes it harder to notice the quieter, but more dangerous attack.
Security through obscurity actually is security, and is perfectly valid to use with a defense in depth strategy. The problem is when obscurity is the only defense.
I agree, these attacks are looking for systems that have pretty default security, and by running on a different port you avoid all this automated chaos because you're non default now. Like scam emails with typos, a way to filter out the naïve people.
It's too much bother to go find it, and the bozos will just move on to the next machine with port 22 open.