I doubt that any islamist or potential recruit really cares about the theological credence that the west gives them. The islamists are apparently very good at doing this all by themselves. So I have no idea what benefit there could be in not talking about these issues publicly as an issue in current Islam. I reckon that you actually agree with that, because your argument that Wahhabism is a relatively new strand of Islam is part of the discussion that I was alluding too. And the audience for such statements are not non-muslims in the west. It's the Wahhabists and potential new Wahhabists who would say to you that it does not matter at all that it is a new movement. Not talking to them publicly about that or say barely more than "you are wrong, and this is not Islam" out of fear that any discussion would lend them credence is a shitty strategy in any war of ideas, and has never worked ever.
What do you mean by "discussing these issues publicly"?
The governments of the West have had ample opportunities to lambaste Saudi Arabia, Wahhabi capital of the world, and its partners for their role in spreading/funding such severe interpretations of Islam.
No country says anything to them and I sincerely doubt it's because of Islamic/religious sensitivities.