They aren’t breaking it.
They are making messaging across smartphone platforms
intercompatible. Using an open, standard-based system (that doesn’t require third-party apps and as registering and sending all your messages through Meta‘s WhatsApp).
Which is a great thing for consumers.
Their ecosystem won’t be going anyway. Apple‘s decision to support RCS is likely pre-empting and preventing regulatory action
Apple is in the business of making money - not in the business of sending messages.
They are, in fact, so much in the business of making money that they‘ve broken their ecosystem by having iCloud being
operated by a Chinese company in China and given the
encryption keys to China.
That should tell you how likely they‘re going to give up 20% or so of their worldwide revenue.