Regardless of the merits of Apple's actions as regards technical interoperability I feel compelled to point out that this in particular is a cultural problem, not technical malfeasance. RCS users still appear as green bubbles and even if the lack of functionality has been remedied the stigma has not. People at my lunch table 20 years ago were drawing artificial distinctions between "MP3s" (portable DAPs) and iPods because the latter were expensive luxury products and the former were not. The same thing is at work here because owning an iPhone is a proxy for one's socioeconomic stratum. I own an iPhone and as soon as an Android user appears in an iMessage group chat some joker immediately makes a green bubble quip - no degraded picture message required.
People that define themselves by conspicuous consumption don't care about interoperability. They care about brand recognition.