Get a dual sim phone and run your own cell phone network inside your home.

(don't actually do this).

Carrier support vary, but you could use VoWiFi.

Which is great until your power/internet goes out, and you need to make an emergency call from inside.

Just configure the cell phone to use VoIP.

If your carrier supports this, of course.

I don't think this has anything to do with the carrier? On Android you would just add a SIP account and then set it as the default for outgoing calls.

Or vote with your wallet and switch carriers or use third-party VoIP as your primary number.