Any game you play, particularly the ones running through distribution platforms like Steam, is wired up with enough telemetry that it would make Windows 10 blush. And they run with full privilege a lot of the time, too.

So if you are on Windows 7 'for privacy considerations', but use it as a gaming machine, then I have a bridge to sell you.

>so if you want to do gaming Windows 7 is your best choice.

maybe for next year or so. For one, it's reaching EOL so no security patches. There's extended support to 2023 but it costs $$$ and it's uncertain how reliably you could pirate it. Even if you ignore security patches, you're going to have to deal with developers dropping support for windows 7, so there are going to be more and more games that require windows 10, and getting updated graphics drivers might be tricky.

Not really. There are games that actually do not work on Windows 7 anymore. Also, there are things like the Vive Wireless VR adapter that works only with Windows 10.