I use Google Voice for this reason, so that you need to authenticate with my google account to modify anything related to my phone number. It's not perfect sinc

I use Google Voice for this reason, so that you need to authenticate with my google account to modify anything related to my phone number. It's not perfect since there is still an internal forwarding number they could sim swap on, but it would require them associating the two numbers first, and I don't use my t-mobile number for anything outside being the forwarding number for google voice.