All I'm going to say to this is....
You people still use SMS?
I've explicitly told people not to send me text messages. The protocols are old and shit compared to other instant messengers. I'm on Google chat, telegram, signal, discord, slack, teams.... Find another app to talk to me with. I generally don't care which one, but I actively refuse to sign up for or into any Facebook/meta/Zuckerberg properties. If you use something I don't that isn't owned by the zuck, I'll probably sign up so we can keep touch, but for the love of God, not SMS.
Look, SMS was great when phones didn't have internet on them. It was a quick and easy way to send updates and chat while away from your cable/DSL/dialup (whatever you had at the time). Now that data is the primary use for a mobile phone plan, just use a more robust IM app.
I also have about six or seven phone numbers, which I give out to different groups of people for different reasons, plus a phone number on my mobile which nearly nobody knows. All my other lines (all VoIP lines) ring my cellphone number. Texting from my VoIP line is not fun, but it does work. Multimedia messages generally get lost and RCS is just encouraging the use of something that should have been killed off.
I'm partial to Telegram and signal since they mainly operate by phone numbers, but I can make "voice" and video calls over data rather than having to use my cellphone directly; which allows me to call from my computer, laptop, phone, tablet.... Literally any device that can run the program. So if my phone is lost/damaged/stolen/whatever (unavailable for any reason), I can still send messages to you and call if needed.
If everything is tied to your cellphone number, and that number becomes unavailable for any reason, well... Get fucked I guess. Your SIM stops working, your phone dies/breaks/gets stolen, your provider decides to fuck your account up or charge you a fortune for no good reason and cuts you off, your provider has a major malfunction and stops servicing clients in your area.... Literally anything goes wrong with the one system you use and all your SMS bullshit goes away. Stop. Using. SMS.