[vetinari]

With phones, it's easy - do not sign in with Google Account. There's no need to flash custom firmware, getting custom hardware, etc. Just do not use your Google Account and be picky about the apps you are going to install.

Yes, it is possible to use Android phone like this. I used it for several years this way - my contacts, calendar and email came from Exchange clone (Kerio) using ActiveSync.

The freaking out regarding Windows is, that you cannot opt out. You don't sign in with Microsoft Account? Does not matter, it will send data anyway. You turn off everything, that is possible to turn off? Does not matter, it will send data anyway. And that's all for something, that was not necessary in older versions - the impression is, that something was taken from you.

See the difference?

[cptskippy]

Actually it's not that easy because Google Services will transmit data back to Google even if you're not logged in. At a minimum it transmits back statistical information but it's not entirely clear what is sent. Which is just like with Windows 10, we don't know exactly what's being transmitted.

So from what I can tell there is no difference.