This happened last year and it was a 2018 CPU (APU?): AMD Ryzen 5 2400GE. It’s a low power 4 core hyperthreaded CPU/APU. Now searching the web for info I see that it was unsupported by Windows 11 from the time of release (2021) - see thread linked below. That means the CPU was a little over 3 years old at that time.
Some comments indicate that it may have been AMD’s own recommendation, but still. I was able to return the machine and got one that was compatible, but it was still an eye-opening experience that showed me that Windows was no longer like the old unrestricted Windows that would run on any PC hardware that could run any recent version of Windows, even if dog slow. Windows is now like MacOS with artificial hardware restrictions, so what’s the point of Windows anymore? I can have Linux for games and MacOS for any software I may need that’s not able to run on Linux.