That Apple "lock customers into using Apple’s official app for texting" is a lie. I use several different SMS texting (some also voice call) apps on my iPhone,

That Apple "lock customers into using Apple’s official app for texting" is a lie. I use several different SMS texting (some also voice call) apps on my iPhone, in order to keep SMS numbers as required by various segments of digital life apart, as well as to serve as the "mobile" number for SMS on my contact info. For a decade my iPhone's primary voice and SMS line were even an original "Grand Central" number before it was acquired by Google Voice. If your preferred number is stuck on your iPhone, you can port it to any app backed by a service that supports porting, then keep using your number not just on that iPhone but anywhere you run the app.