I've had a win10 PC for about 4 months and recently switched to using it fulltime. Since I don't believe in the "rite of reinstall" that many seem to be performing with their windows every one or two years, my old Windows 7 install was almost 10 years old. In the 4 Months of using Win10 I probably had more issues than in several years of using Win7. I believe in "never touch a running system" and with its mandatory auto update bullshit Win10 just isn't as well suited for that. There is a small hand full of things that are better on 10, but if it wasn't for an increasing number of things no longer working on win10, I never would have switched voluntarily. I totally understand anyone who clings on to win 7 till the last possible minute. When I went through all the customization settings regarding data privacy and what not, I felt physically ill reading what the windows 10 defaults are allowing microsoft to do. I think it's absolutely insane that people don't object more vocally. I'm not able to give any exhaustive details, do your own research if you want to know more. In the end we don't really have a choice anyway and it's yet another way in which we are slave to things outside of our control. Really makes me sick where everything is headed and how complacent all the consumer sheep are letting it happen.
I get that, the privacy things are indeed an issue.
As for stability.. i have the opposite experiences: windows 10 a more smooth experience vs windows 7. The latter had often blue screens, weird unexpected errors etc.. not with windows 10. Sure, i waited some months before the upgrade, to have the first issues reported to be ironed out with updates.
However...if you keep staying on a not supported platform, iit means developers will also stop (or already have stopped) supporting it too (sooner or later). Which means tinkering to get it going, and if things break, you cannot call for support. so in technological sense you get behind further and further. This is especially the case if you are frequently buying new software etc.. (or update third party software frequently)
E.g. Kontakt 6.7 is already more harder to install on windows 7, than windows 10.. since windows 10 is supported.
Also (if the machine is online), staying on an unsupported OS, is a higher security risk, because the OS isn't updated anymore.
I would be very much pro cross platform the broad sense.. : Windows, linux distro's, macos and at times even free/open/netBSD for desktops. So you have the freedom to use whichever OS you prefer.
Don't like current windows? go to the alternatives.