I see your point, but I'll add that telemetry is focused on making sure stuff works, whereas selling ads based on your data is focused on making money from you.
Last I checked windows now has ads in it. Those ads may currently be totally untargeted, but that's a small comfort and I wouldn't count on it staying that way forever.
Motivation is irrelevant if I don't want to share any data as a user.
edit: Besides that, the telemetry service has caused multiple problems on different systems already. I just don't see any results from it compared to previous versions of windows.
Telemetry can be disabled on Enterprise: https://www.kapilarya.com/allow-or-prevent-telemetry-in-wind... but I agree it would be good for Microsoft to allow this to be disabled in Pro.