Does suggesting someone should learn to spell constitute abuse?
It probably does count as abuse. But I understand how irritating it is when people write in text talk. It makes the question/answer so much harder to read. If you feel you need to say something when people do this, perhaps try something like “it’s really hard to read your message, please could you write it without the text talk”. Then you cannot be reported for abuse, because you are still trying to help them, but also pointing out that their message is difficult to understand.