The transition of the major social networks over the last 10-15 years -- from being a space for friends to interact to being a space to consume content produced by "unconnected" entities like influencers -- has created a huge opening for someone to claim the friends and family network. There is no one better positioned (at least in the U.S. where iPhones are the majority handset) than Apple.
But the point remains that a cynical UX/technical/business decision that does not need to be so is rending real relationships between actual people. If Tim Cook had the power to render anyone who didn't pay him $400+ mute to their friends and family through some sort of black magic, we'd call him a comic book supervillain.
Maybe RCS doesn't do all the esoteric iMessage stuff but it doesn't necessarily have to, half those extra features are gatekeeped on having the latest iPhone or whatever and so they don't get used as often.
This is why we need legally mandated interopability for call communications platforms above a certain size. It's absurd that the situation today is worse than the early 2000's where you could use one program to talk to your ICQ, MSN and Aim friends.
Before there was the pandemic and 'Zoom Fatigue' there were other applications such as Skype, Google Meet, WebEx, Go2Meeting and many more that went through a variation of Doctorow's 'enshittification cycle' although it isn't so much that these became commercially exploitative but rather the honeymoon period ended.
If, for instance I want you to try a new "meeting" program your response is likely to be "this could be such a hassle" and the vendor has a strong incentive to make it work well so I can say, "Remember how well Skype used to work ten years ago? Zoom is like that now". In that early phase the vendor invests in quality, once it has an established user base it is 'competing' on the basis of dominance of a two sided market and there isn't any need to invest in quality. (In fact, investors insist on disinvestment because they want to take profits after years of losses.) Eventually it gets so bad that even the two sided market dominance can't save them anymore and a new competitor comes in.
If chat and messaging programs were interoperable, vendors would be competing on quality instead of relying on two-sided market dominance, and we'd have seen the user experience improve rapidly and dramatically over the past 20 years instead of going sideways. I mean, "remember how good ICQ was?"