Until cross platform messaging is a good as iMessage and FaceTime from an iPhones user’s perspective it’s going to be bad.

I have only ever used an iPhone (ignore non-smart phones) and have been weaned entirely on Apples stock apps. Conversely almost everyone I communicate regularly with is also an iPhone users. I do use other platform for communicating with non-apple friends but the experience is significantly poorer.

I couldn’t say how many people existed within this almost exclusively Apple ecosystem but I would hazard a guess that there are a few.