I don't think they'll ever go away, and that's because of the nature of short-form text communications. You need to express emotion, something language is bad at doing in short-form. Longer expressions can have great flowery emotion, but "im gonna kill you" can mean a lot of different things depending on the emoticon or emoji that follows it. And that's really important.

Some people write long messages to convey emotion. Others use ambiguous phrases and follow it up with a quick expression of emotion to set the context.