Relying on telemetry has been the biggest mistake developers decided to do in recent years. In the vast majority, only the most technically illiterate will keep telemetry enabled. For anyone with enough knowledge and two braincells to rub together, telemetry is an euphemism for spyware, so of course they'll do everything they can to disable it (also see all the Windows 10 "shut up" scripts, etc - people would rather run random scripts from the net than allow telemetry, even if doing the former isn't exactly that smart to begin with).

Relying on telemetry is heavily biased towards people who do not know what telemetry is.