Google has been working on replacing the ad-hoc Signal protocol with MLS since before Apple announced they'd support RCS, it would have happened anyway.
It's more likely Apple was made aware of the spec/Jibe/Messages roadmap when they finally got on board, decided not to target the latest UP version for some reason, and realized implementing the current E2EE scheme would be wasted effort given it would need to be revamped within a year. The iOS RCS client is still pretty far from being provisioned worldwide.
It's more likely Apple was made aware of the spec/Jibe/Messages roadmap when they finally got on board, decided not to target the latest UP version for some reason, and realized implementing the current E2EE scheme would be wasted effort given it would need to be revamped within a year. The iOS RCS client is still pretty far from being provisioned worldwide.