I would prefer they just require Apple implement RCS (which they've already agreed to do), and -- crucially -- require feature parity with Android's RCS implementation. Which means standardizing Google's proprietary E2EE extension, and implementing that as well.
While I'd prefer being able to install a standalone Android iMessage app over the current situation, I really don't need or want another chat app.
End result - Apple is forced to do whatever Google wants.
I find it hard to imagine a company - that cares about its own future - would agree that they are required to implement things that their _competitor_ decides.
That scenario will just hand over the monopoly keys to Google, and we're back to square one.
Apple is adopting the Universal profile. If GSMA wants to add E2EE to that profile then they should. I believe that there was some talk of Apple working with GSMA to add or improve encryption on that profile. AFAIK rcs is licensed out to OEMs and so there are a number of different implementations around. In my opinion it would be better for all if there was a secure standard in place - for all to adopt - instead of hoping that everyone works with google to try to get googles proprietary implementation working.
The only open question (in my mind) is if Google's E2EE extension is intrinsically tied to Jibe. If it wasn't designed to eventually become part of the RCS standard, it could be real messy trying to open it up after the fact while remaining security.
While I'd prefer being able to install a standalone Android iMessage app over the current situation, I really don't need or want another chat app.