Fedora considers "privacy-preserving" telemetry

They address this in the proposal and say that this requires them to do things in a way that is compliant with European law, i.e., any proposals that would be in violation of European law are already off the table. This actually seems like a good constraint - if their devs insist (for good reasons that they set forth in the proposal) on opt-out metrics, their lawyers are going to insist that the data cannot be used for correlation. They can't be tempted to start collecting too much data and defend it with "it's fine because users are consenting."