Every commercial product has an eventual end of support from the manufacturer, so people complaining when Windows goes for ten years and then loses support(and patches) should be seen as very normal. We do NOT live in a time when the operating system is a subscription service that you MUST pay every year to continue to use, or even to get support for during the support period.
So, you don't like Windows 11, yea, there are a lot of things in the world not to like, but then, to expect SUPPORT and updates for something that is no longer bringing in money also makes no sense. Now, the reason for some of the arbitrary cutoffs and requirements for Windows 11 are actually based around corporate politics.
So, why require TPM 2.0, because in general, TPM shouldn't be a requirement for the OS to work, right? Now, consider, at the end of 2017, we had the big Spectre and Meltdown vulnerabilities were announced to the public. Suddenly, all those Intel chips had security problems that couldn't be patched in a BIOS, it was the design of the chips that were insecure. So, Microsoft put in mitigations. I think on Jan 5th of 2018, that first patch with mitigations was released(note it was a Thursday, not a Tuesday, so the security issues were REALLY serious.
Now, AMD did have chips out there, Ryzen was still new, and did NOT have the security problem that Intel had. Spectre, being about speculative execution, was an issue for all chips(including most non-x86 based), but AMD wasn't hit nearly as hard. I think first gen Intel took a 40 percent performance hit with that security update when it came to I/O related stuff, because the OS had to handle the vulnerabilites. Then the next year, yep, more security problems were found, more mitigations went into Windows to deal with it. And the next....the new chips did address the vulnerabilities, so security improved, but Microsoft had to continue putting more mitigations into Windows, and this made troubleshooting and development more difficult.
So, with Intel being the leading CPU maker, but the source of MOST(not all) of the security issues, Microsoft couldn't come out and say, "Yea, Windows 11 won't support older insecure Intel chips", because that would just cause a major rift between Intel and Microsoft. So, how to address the situation...oh yea, you need TPM 2.0 for Windows 11, that way, the security problems in Intel chips just gets filtered out as those 7th gen and older Intel chips just weren't officially compatible. AMD Ryzen Zen and Zen+ based chips were caught by this as well, even though they weren't the real reason for the TPM requirement, Microsoft still didn't want to point to Intel as the reason for it.
Now, there have been some additional changes over time. MBR vs. GPT/EFI for being able to boot. MBR has been a legacy approach for quite a while at this point, and Microsoft finally made it so only EFI would be supported. While it isn't a problem to convert from MBR to GPT(mbr2gpt is included in Windows), if you do this without the BIOS supporting EFI, you do the conversion and you now can't boot, and you can't undo the change back to MBR. Microsoft does not want to deal with supporting THAT situation either, but 24H2 I think is where Microsoft did the cutoff for MBR support, so even if you get around the supported CPU issue and TPM 2.0 issue, if you don't have EFI support in your motherboard/computer BIOS, you will run into signifiant problems going forward.
Being held back by people who hold onto stuff well beyond its time isn't good for any company, so, a slow process of filtering out old and outdated stuff really isn't horrible, even if you don't like it because you are the one holding onto computers for 10+ years. SUPPORT for old stuff is fine when you don't have to pay employees to provide that support, but if you need to pay millions in wages to continue to update and support a product that doesn't actually bring money in really does become problematic.
Note that I'm not really advocating for Windows 11 as much as showing that it's actually reasonable for Microsoft to drop support for Windows 10. For many products out there, you won't see manufacturers continue to make parts for older models, so they stop making the parts, warranty coverage is limited for how long the warranty will last, and if you NEED to replace a part, if it's over ten years old, you may find that finding parts may not be all that easy, depending on how many parts are out there and available for purchase. If you complain because your 10+ year old car doesn't have new parts being made by the manufacturer, then you haven't paid attention.