I’ve never understood the messaging interop angle when there are so many non-phone network based messaging apps available. It’s just always seemed the weakest of the arguments against Apple w.r.t. the iPhone. SMS/MMS/RCS standardization was historically a train wreck so it made sense to me for Apple to just support the minimum and be done with it. All of my groups chats that involve a mixture of iPhone and Android users has usually been on something like WhatsApp for this reason.

The other points seem much more specific and actionable.