Opt-in telemetry not executing for users who would like it to be executing, because they don't know about it or forgot, makes it an under-advertised feature.

Opt-out telemetry executing for users who would not like it to be executing, because they don't know about it or forgot, makes it a spyware.

The rest of the discussion only makes sense to have if you agree there are circumstances when implementing spyware is justified.