A rather long list of use cases (for Go) is at: https://research.swtch.com/telemetry-uses https://research.swtch.com/telemetry-uses It doesn't take that much i

A rather long list of use cases (for Go) is at: https://research.swtch.com/telemetry-uses https://research.swtch.com/telemetry-uses It doesn't take that much imagination to come up with useful use cases. I'm sure there are many for Rust, too. Linux is even more low-level, and telemetry would undoubtable be useful there too. "We don't break userspace" has always been interpreted flexibly – for example it's fine to break userpspace if no one will notice – or rather: if it's expected that no one will notice. But it's almost impossible to say if anyone will notice, and breaking changes are frequently rolled back because it did break stuff, causing wasted time and frustration from all sides. Whether telemetry should be done is a different discussion, involving upsides, downsides, and trade-offs. But that it's useful for almost all software with significant widespread usage is hard to deny.