Babylon open world games

I found video on youtube and i was surprised by the level of optimization. There is really beautiful and large open world, but there is no evidence that this is really the babylon. I want to ask if really webGPU able to create such a big world with such a good distant drawing level ? Maybe someone want to share projects like this, would be interesting to see.

This would probably not run on tiny mobile but I guess it should be doable for desktop.