Opt-out telemetry is indeed awful, no matter how righteous one feels in the cause to get it.
I agree that opt-in telemetry however is useless.
Thus, the only ethical and useful option is forced choice; i.e. present the user with two unselected options where a decision between them must be made.
This is e.g. how Apple designed its usage data option for the Apple TV, AFAIK. Two unselected options, given equal weight and styling etc.