This was the subject of a reply of mine to Tatiora's October post on Windows 11 Updates that I think merits a separate thread.
I've been advised by my tech support company to not install Windows 11 under any circumstances. A major reason for that is that I (and my office network) deal with protected health information and Windows 11 is not only not HIPAA compliant but opens your computer to all kinds of background third party access. MS has decided to go the way of Facebook and make you the product which they will sell as the primary method of sustaining their business. The 'upgrade' may be free but orders of magnitude more intrusive, mostly silently of course (the fine print applies when you click Agree).
Windows 11, per my tech, also is a major step toward forcing all your application purchases and subscriptions into the Microsoft Store, a la Apple. They are steadily making it harder & harder to install anything from outside their controlled ecosystem. They actually trialed this approach with a version of Windows 10 called Windows 10S. I learned of this when we purchased a Surface which turned out to have that OS for a dedicated purpose servicing a biometric device early this year. Initially I thought the "S" meant a version specific to the Surface but it turns out the "S" means Store, as in Microsoft Store. Our tech had to force an install of a regular version of Windows 10 before the software for the biometric device could be installed (it obviously wasn't available on the Microsoft Store). There were also incompatible drivers for things like our network printers & Bluetooth devices. The latter issues are probably cleaned up a bit in Windows 11, but beware.
A good example of where this will likely lead is the recent behavior of Adobe regarding Adobe Acrobat Reader DC which is the subject of another post here. They already have the ability to reach into your computer uninvited and steal paid-for software from you.
Enjoy the brave new world of computing and Happy New Year!