Because telemetry as implemented and spying are in fact very very different, and conflating the two is why "noone cares about privacy". When your giant conspiracy wall is "Manjaro knows a user in north America clicked on the start menu more often then typing into a quick search box" and you refer to that as spying, you hurt the actual cause you claim to support. Badly.
The same is true for Microsoft, ive been asking for years for any concrete proof of spying a normal human would care about and what I usually get is the Microsoft terms of use, a legal document that reflects reality less than the average legal document, and the average legal document is basically covering your eyes and hoping nobody sues you.
And because I think the correct way to dick swing in this community is as follows...I also use arch ๐ (well endeavour, but I think I still get dick swinging credits)