I can only speak for myself. I used to play Second Life when I was a teenager. A lot. What it was is less of a game. There was no grinding, no objective, and more of a chat room with a built in 3d modeler and scripting language. Everyone I played with grew up either ended up as a programmer or a 3d modeler of some stripe.
And I see the same sorta energy in people playing VR chat today.
What I think you miss as the usecase here is people who aren't quite happy with their identity, or are and choose a different more extreme representation. The difference between being yourself and being a fox for example.
Plenty of people in the world today are lonely, and online connection is what fills the void. They don't have kids, dogs, or spouses. They're a sixteen year old in the middle of nowhere, or a socially anxious programmer living in a shoe box.