why would the hardware layer bubble pop if the demand for hardware will still increase (or not change)?
TSMC will still make massive bank because they're the bottleneck. That bank will be squeezed out of companies dependent on TSMC.
I still don't understand how models being commoditised implies the hardware (NVIDIA) itself being commoditised.
What is the exact mechanism that causes NVIDIA's profit to go lower?
Do you mean to suggest that the bubble popping will simultaneously commoditise models as well as inference hardware?
They are completely different layers and have almost zero correlation. I see no indication that hardware also gets commoditised.
And it's correlated with the other bubble dropping because chip cost will matter a lot more once the margin of tokens is tight.