MySudo is VoIP so it will have the same issues, and I already have a few privacy-respecting JMP Chat XMPP numbers for personal, burner, and business.

JMP.chat

Your phone number on every device

I'll probably go back to Google Fi for my front facing main mobile number. It's not as private as silent link promised to be for 2FA, but I already have a privacy.com virtual card on GP, so I can still keep my debit card info protected. They have good coverage at reasonable prices, and the 2FA will be bulletproof.