Well if we go MW we may get that because of http://fallout.wikia.com/wiki/Hairy_deathclaw
This ^
In Fallout Tactics you can have deathclaws in your squad :mohawk:
They are a different sub species of deathclaws or the locals call them deathclaws and they are a different species entirely but they can be on your team and they arn't that smart.
Having ones as a companion in a future game would be fine. Raising it from a young deathclaw to advlt I am against.
Edit: I am not going to get dragged into a debate about canon here so don't bother.