Virtual Reality

I mean, a corporation will always cover their ass on the label while happily marketing to groups below their recommended age range

And you're right that we don't know if there could be problems... You can't do this kind of research on toddlers for ethical reasons. The only way to find out is to either study issues or wait for a good slice of the population to grow up using them

That being said, it's just concerns - something we always have with something new. I'm sure extreme use could have some psychological effects, there could potentially be some eye-related development problems... But it mirrors our sight and movement at a time when this kind of body coordination is crucial.

Playing outside is IRL is probably best, but movement games on a 2d surface aren't going to give you the same coordination. And in virtual worlds with various physics, I could easily see this leading to deeper spatial awareness

It's a judgement call. It's not a clear and dry risk to development though - "normal" amounts of conventional screen time certainly seems to be though. The ideal parents would be hands on and frequently exposing their kids to many different IRL activities... But using VR to fill in the gaps isn't a terrible idea (without further evidence)