Earlier quoted context omitted.
And I bet in classical Apple style, they would definitely gimp the Android iMessage app restricting some features, just to spite Android users and try to force them to buy iPhones. Android users will still be second class citizens so the transition off Whatsapp or Signal will not happen.
Now that would be the stupidest thing to do, why would they want Android users to think that Apple services are broken? Shouldn't they do the exact opposite and have a really good app giving Android users a glimpse of the holy iPhone land?
If iMessage was as good on Android as it is on iOS, why would Android users switch? Or why would people buy iPhones in the first place?
Internal documents from Apple prove that they had builds of iMessage ready for Android but never released them because Apple knew iMessage was one moat that kept the userbase loyal and annoyed Android users enough through the bubble color discrimination to make them switch to iphone. Like parents heading down cheaper iPhones to kids instead of buying them android phones so they can all use iMessage.
FaceTime is currently available for Android users as well but the experience is shit to prove Android is poor and that iOS is the only way to go for the full experience.
I'm not making all this UB but tech YouTubers extensively covered Apple's iMessage moat with proof and arguments and how this works in their favor so I won't go into all the details.