then why cellphones are not treated same way? SMS/calls should be analyzed and then people should be banned from network if something is “wrong”. And by “wrong” I’m not talking about organising a crime such as terrorist attack or something.

Cell phone telco propviders have monopolies on radio spectrum that come with certain obligations, regulations, and conditions. That's in addition to inheriting the rules from land telephony and public infrastructure/title II stuff.

You can bet that this kind of thing will happen if they can make it happen though.

Yeah, I use Riot/Matrix now and I can self-host it if I get disabled...but they don't mind if you don't give them a #/email so its really less of an issue there.