Well, they need to know your device rotation to serve you the perfect ads! /s
Seriously, I wouldn’t mind them knowing a thing or two about me, when I’m using their services. But tracking everything, just because they can, is just obnoxious. If you would translate this to the real world, you would definitely get arrested when you would stand on the corner of the street, noting down everything you see, every dimension/detail of every person walking by. You would be labeled “creep”. But if Facebook does it, governments go like: You can build your new data center right here, don’t mind the measly peasants that currently live in the village nearby