What's a good VR headset these days (and other VR hardware questions) ?

One if my kids wants a Meta Quest 3 for his birthday, and I am only vaguely familiar with VR hardware, and on top of that I'm wary of everything Zuckerberg.

1. How are the ecosystems? Does the choice of brand lock you in or out of particular titles? I suspect his main goal is to play gorilla tag and similar.
2. Is Metaquest 3 an objectively good/decent product? What are some viable alternatives?
3. He's got a decent phone and a half-decent PC. Will the same headset work for both?
4. How much GPU (if any) is required to drive one of these decently?

EDIT: He's looking at the 3S version. Looks like 3 is more in line with steam frame. His birthday is mid-march.