Earlier quoted context omitted.
At least it doesn't only run on Apple devices, like the complete joke that is FaceTime.
[Here lies a substantive question that was posed to a content-free comment. Edit lasts longer than delete, so you now get to read its depressingly gray tombstone. Let's reflect together on this.]
That's a very strong defense of a piece of software that deliberately prevents you from communicating with people that haven't bought the same piece of electronics.
Think on that for a moment - "Sorry grandmama, I can't send you iMessage or talk to you in person since you didn't spend your pension on an expensive Apple device."
For something as fundamental as human-to-human communication, closed, single vendor, protocols and systems deserve every criticism (and yes, Google deserves it as well).