The most common emoji I see among kids is (Face With Tears of Joy) or (OK Hand) (apparently ycombinator doesn't support UTF-8). I don't know of any ascii that can do those. (FYI, I'm 28 and I often chat with my younger cousins who are in their mid-teens at the moment.)
The debate is not "are emojis widely used". Yes, of course they are. The question is "opened a whole new way to communicate with each other", which is what I responded to.
I say, no, they haven't. I can convey the same emotions with ascii. I can convey the same emotions with written text. If you want to prove me wrong then fine, but don't re-frame the discussion.