The Wii was heavily marketed as a family entertainment system. A 'Family Computer', if you will. It's even in the name. People were buying it because it's something your grandmother could play alongside your five year old son. VR is still marketed as ages 13 and up, gives some people nausea and can only be used by one person at a time. There's also extra hygiene concerns that make them awkward to use at parties as you have the extra step of wiping the headset down between users. The controllers are also pretty intimidating for new users because you can't see them. I was showing PSVR2 to my dad and told him "Push R2 to select" before realising that if you didn't know where the R2 button was already, you had no hope of finding it because you're physically incapable of seeing the controller.

It's a long way from the ultra-casual Wii experience.