The real problem isn't the shapes (there's plenty of free meshes out there), it's making them interactive, which is a complicated problem that extends well beyond the capabilities of our current generation of LLMs. Just look at Roblox: it's successful because you can make the world do stuff. But we can be pretty sure that just making VR/AR Roblox doesn't make a killer app.
The challenge that a killer app for VR/AR needs to overcome is being more than a glorified art gallery.
2. I think Apple has enough money to fund both initiatives to be alright
3. The unit economics of LLM products are still not proven and even when it is, any hardware product will more than likely have higher margins. Do you think people are going to give up the iOS ecosystem for Android based on an improved voice assistant?