I haven’t used non apple earphones for awhile but the seamless connectivity performance of AirPods would suggest this was done for performance, not to deliberately lock in devices.
This 2020 paper is great at breaking down some of the extensions: https://www.usenix.org/system/files/woot20-paper-heinze.pdf
In their defence, they went with Lightning shortly before the USB-C spec was finalized. Then, to avoid their customers being screwed over by constantly changing the connector, they kind of had to stick with it for a decade.
People will complain if they push features that are ahead of the spec, and they'll complain if they let the spec be finalized before they use it. Being guided by "What's the best we can do for UX, assuming out users are our users in every product category we enter" seems to be their reasonable middle ground.
Then it has to accomodate every other intersted party, many of which hate each other. Apple has always been a bit of an odd duck ("Think Different" has been internalized for some time), but Verizon actively hates OTT messaging as they can't charge for it. Samsung would rather run their own RCS implementation to create and advertise "Samsung RCS", and Google can't push too hard without getting EU attention for antitrust (again).
RCS has been stuck in limbo-hell for years for multiple reasons, none of which are easy.
This is a problem no other vendors have, and is solely caused by Apple.
https://www.androidauthority.com/android-iphone-rcs-messagin...