Not a failure to me. It is the most exciting piece of computer hardware to program apps for that I've purchased in the last decade. I understand why others consider it a failure though, and wonder how it would have performed if it weren't so expensive.
My hope was that it was going to pave the way for apple to release a pair of glasses that had some of the functionality of the Vision Pro. I'm guessing this is still one of their goals, however Meta and even SnapChat beat them to it.