there's three options I see
1. No telemetry. Hope that people report things accurately
2. Opt-in telemetry. Hope that enough people opt in to give something statistically accurate
3. Opt-out telemetry. Gives the most data, but can be pretty creepy
Issues with (1) and (2) are that only those who are positively engaged + more technical are likely to opt in or report.
Issues with (3) have been widely discussed all over already