The game they were playing with a regular game pad was an iPad game, not a VR game. Nearly all VR games are built for VR controllers like you get with the Quest

The game they were playing with a regular game pad was an iPad game, not a VR game. Nearly all VR games are built for VR controllers like you get with the Quest, and those are something that Apple themselves would have to facilitate for it to not be a massive hack. The industry already went through this phase, the very first Oculus Rift came with a regular Xbox controller and that idea was quickly abandoned. The Quest has hand tracking but it's treated as secondary to the set of controllers it comes with.