My problems with telemetry:

Scope: if you provide a service which is a "wrapper" for doing other things, I do not want you to collect usage data. Example: an entire fucking operating system

Opt-out by default (or completely unable to turn it off) even if the service or software I'm using is paid: I want to have the ability to say no. Communicate properly what you collect when I get access to the service, allow me to say no and don't hide it in 300 pages long TOSes. I don't want to become your free UX tester when I already pay for the service.

Telemetry-driven development: I absolutely hate this both as a user and a developer. We see there are thousands of users using a feature, but it's a low % in general, so lead decides we need to remove it from our product. I know that those x thousand people will be annoyed, and so am I when I'm on the receiving end of this.

Another reason that is not universal but service specific is making decisions that purposefully keep you on the platform, over optimizing the interface for maximizing profit.