This is very, very, very bad advice. A non-standard port is not a defence. It’s not even slightly a defence.

Did I at any point in my previous comment say that using non-standard ports was my only line of defence ?

Its security through obscurity, which puts you out of view of the vast majority of the chaos of the internet. It by no means protects you from all threats.

Correct. From what I understand, Shodan has had for years a search feature in their paid plans to query for "service X listening on non-standard port". The only sane assumption is that any half-decent internet-census[tm] tool has the same as standard by now.