They put some under-the-hood improvements in 10 that they didn't put in 7, such as a new display driver model and Directx 12.

But that does not make a difference to most people. Industry desupporting of Windows 7 is the biggest con to it.

Eventually, 10 will share 7's fate. So you'll have both 10's regressions and 11's and so forth to live with as long as you're on Windows. You can't stop Microsoft from desupporting and killing their software in the long run.

Microsoft has a multi-decade history of enshitification when they do not perceive any major threats. Internet Explorer, DirectX, Windows Server, etc. all rotted. Some of these are still active and supported, yes, but they all peaked years ago and are aging poorly. Microsoft doesn't really do the labor of love thing much when customers are bagged.

Linux may be able to dethrone them to an extent if it can reach an ease of access/UX that most people are comfy with. And it has made huge strides over the years. It can also run most Windows software very well.

Mac is still priced very high and still feature-limited and a 2nd/3rd-class citizen when it comes to platform targeting. Offering lower priced conputers would make them a pretty big threat I think.

I think ChromeOS is a decent threat to Windows but it loses tons of features vs all the other options. At least it is really cheap and easy to use.