Without doubting what you are saying, why under that logic of GPU bottlenecking would Apple not have used an M2 Pro or M2 Max chip in the AVP? Apple could have more than tripled the GPU cores and bandwidth using M2 Max, and the $3500 price of AVP would support such a higher end chip.
Price? Power consumption? heat? battery life? Wearables aren't quite as simple as "stick the biggest baddest processor that will fit in it".
My bet is most likely heat and power consumption. The M2/m3/m4 max consume a lot of power and put out a lot of heat, relative to the space available to cool the thing without a fan in a head mounted device.
It's not that the device couldn't use the power - more that it would likely introduce a series of other problems; from what i understand the vision pro is pretty heavy on your face as it is; it would be worse with more cooling (increased weight) and even worse if it had a fan exhausting hot air near your head (comfort, fans small enough to fit are noisy), which will already get warm with something like this stuck to your face (based on my experiences with the quest2, quest 3, hololens and PSVR2).
It will likely get something similar power to m2 max when that is available in something smaller and more power efficient - or if the processing is offloaded to a part of the device that wirelessly connects to the headset so that hotter/heavier component is not carried on your head. But - that poses its own challenges; VR is very sensitive to latency and moving components like that out of the headset may introduce additional latency purely due to the wireless connectivity...
Depending what is going on, my 6900XT struggles with VR at times, and that's a 300+ watt GPU that will smoke my m4 max at GPU things.
We've got a very long way to go with AR just yet, which is why its clear to me that this is an early adopter device for software developers and curious people to play with - it's not a mass market device because the technology simply isn't available to get the level of visual fidelity in a mass market product yet. From any vendor. everybody is making different compromises and one of the compromises apple made was cost - they didn't build down to a price so much as say, Meta did with the quest series.
As to the cost of AVP being able to support the M2 max (discounting the heat/packaging concerns above)? Not so sure on that. The thing has expensive sensors, screens and lenses in it. It's not subsidized with user data like the quest series by meta is. Its a tier or two above what you'll get in any competing ar/vr headset and the price reflects that. The M (+R1) series SOC is a fraction of the actual BOM cost of that headset and i really doubt apple have a lot of margin on it. It's expensive because its expensive to make.
