Blacklist everything then whitelist the IPs you know you’ll be connecting from (work, cell phone, etc). I don’t connect from random places usually. If I need to then I use cellular. You might be better off with a VPN if you need to connect from random places.
I see, thanks!
Is there any concern with whitelisting a cellular CGNAT’s public IP? Presumably that would potentially whitelist thousands or tens of thousands of other mobile devices at once, wouldn’t it?