That is why there is a company selling laptops where the OS is the browser, and another one doing the same for smart TVs.
Because if it's the web, Google sees it. And if everything is the web, then Google sees everything.
(I remember several awesome hobby OS projects ported KHTML to get a really good browser back in those days. It was a really solid and portable codebase and much tidier than Firefox.)
Google sees everything that is public and everything that uses their ad network, including data from apps that don't use the web at all.
Can't remember the last time I used Windows for anything more than launching Chrome and Steam...
I guess you would be better off with SteamOS then.
If not for DirectX and Windows-only games, I'd totally ditch it. Maybe when Proton gets there.