You're sidestepping the argument. To stay consistent, you'd have to run a local mailbox service, DNS service, redundant data backup/storage service, audit your browser code, etc. Not exactly "most people".
In any case, IMHO the stronger argument is that just because webapps spy on you doesn't give Windows any right to do the same. Unfortunately, a lot of web companies have shown that people will throw money at you if you attract enough users, and sell their eyeballs or habits.
Windows and OEM software/drivers are on the local machine.
In a restaurant, I expect other people to see what I eat. In my own house, I don't.