'incompatible' hardware will be dirt cheap, and 8th gen or newer will sell for more than it would have otherwise--especially if tariffs jack prices up on new hardware.
i have a couple dozen older systems here. most were given to me before win11's requirements were known. fixing and flipping them for a few bucks was a small but relatively steady income stream, but not anymore. hardly anyone wants them.
the couple that are new enough to be blessed by microsoft will be kept, and i'll hang on to the better ones of the rest (like skylake, kaby lake) to put linux on. everything else will end up at ewaste recyclers even though there's absolutely nothing wrong with any of them other than the fact that a profit and 'shareholder value' driven megacorp says they can't be used anymore.
Maybe the tariffs will serve to cull a bit of the consumist impulse the US suffers of.
Regarding if a machine is desirable or not: I'm still seeing Windows XP machines being sold today for over 100€. No monitor, no peripherals, no nothing: just the machine. And people needing a machine to type a report, do a spreadsheet, do basic office work, with no other option, pay for it.
i run my machines until they stop working, period.
It's fairly trivial to bypass Microsoft's hardware requirements for windows 11 afaik. Just install via Rufus and click the relevant options. I agree with you that MS should have made these optional recommendations though, we shouldn't have to use third party tools.