We don't need that at all.
RPG suffices.
Clearly it doesn't, since I've never seen anyone agree on what RPG means. If people communicated what they meant by the term, there would be less confusion and fewer arguments. In any case, if that's your argument, I assume you think 'open world', 'linear', and 'sandbox' are also redundant terms. As well as 'action RPG'.
You have to classify games.
Yes. But we're only allowed to classify them the way you want us to, it seems. What are we going to do when you're not around?