There's another part to the exclusion of old hardware, which is that modern chips are a lot more reselient against crashes according to the telemetry Microsoft collects. The same is true for secure boot and other security lockdowns every Linux user disables. You could make the argument that this means that Microsoft is failing to provide stability for this older hardware, but it doesn't necessarily mean that it makes business sense for MS to put money and resources towards resolving the issue. Not making Windows 11 available on old chips doesn't hurt sales, helps them boast with great stability and security statistics and barely makes a dent in their reputation. Most people with a negative opinion of the company here were hating on Microsoft long before Windows 11 was even announced.
The TPM story makes sense from a Windows Hello standpoint. I don't think there's any doubt that the hardware trust system is more secure than the previous system. However, that trust is completely useless because Microsoft STILL doesn't enable Bitlocker unless you pay extra. It's current_year and Microsoft still hasn't brought data security to the masses. This is an area where proper use of the TPM can be benefit users massively.
Linux is having the exact opposite problem, I want to use my TPM and secure boot to leverage the hardware security built into my devices but it's as if every part of the Linux boot chain has implemented some kind of limitation to make the process difficult. Bitlocker works great, and I want it on Linux too, but nobody writing code for the Linux ecosystem seems to share my preferences here.