Microsoft's strict compatibility requirements for Windows 11 mean that a significant number of PC owners will be unable to upgrade to Windows 11, even on relatively recent hardware. Meanwhile, the company has spread the message that installing Windows 11 on an unsupported PC means it won't be supported and won't be entitled to receive updates in the future.
Which raises the question: If you do a clean install of Windows 11 on an incompatible PC, is your PC really in danger of getting cut off from monthly security updates some day?
Allow me to answer that question with a question: Have you ever heard of FUD? The acronym, short for "fear, uncertainty, and doubt," has been around a long time, but it was popularized in the 1970s as a way of describing how the giant IBM Corporation discouraged its customers from even considering competing products.
FUD is a classic marketing technique used when there's no good technical argument to make against the choice that the customer is contemplating. It's odd, though, to see an example like this, in which the giant Microsoft Corporation is using FUD to discourage customers from installing one of its own products.
Installing Windows 11 on this PC is not recommended and may result in compatibility issues. If you proceed with installing Windows 11, your PC will no longer be supported and won't be entitled to receive updates. Damages to your PC due to lack of compatibility aren't covered under the manufacturer warranty. [emphasis added]
This is, of course, the business-school version of "Gee, nice PC you got there. Be a shame if something happened to it." But it really doesn't say that Microsoft is going to cut off your access to updates; it simply says your PC is no longer supported and you're no longer "entitled" to those updates. That word is a tell on Microsoft's part, disclaiming legal responsibility without actually saying what it will do.
In fact, it would require an awful lot of work on Microsoft's part to configure its update servers to reject requests from PCs based on such detailed configuration information. Doing so would run a risk of snagging customers with valid installations, and it would needlessly anger customers who were otherwise having a perfectly good experience with Windows 11.
Instead, that language is a way of convincing timid customers to retire those old PCs in favor of shiny new ones, thereby choosing the option that puts fresh revenue in the pockets of Microsoft and its OEM partners.
As for the "supported PC" part of that warning, well... Microsoft doesn't directly support Windows PCs anyway. The OEMs that build and sell computers are the ones who have that responsibility. So don't be intimidated by what is, in fact, pretty much an empty threat
This sort of confusion isn't without precedent. Back in the days before Windows 10 launched, Windows skeptics were convinced that Microsoft was going to pull the rug out from updates based on some confusing language about the "supported lifetime of the device." One Windows pundit (with a track record of being wrong about, well, everything) even claimed Microsoft was going to start charging Windows 10 customers for updates within two years.
It's possible, of course, that some future Windows update will cause performance and reliability issues on older PCs, but the idea that Microsoft will punish its customers for following a documented upgrade deployment procedure is, in my opinion, highly unlikely.