I have OTEL + Rust in production, alongside some other languages (+ OTEL), and it is by far more useful and predictable than the others. I often find myself monkey-patching in logging for other language libraries, where with Rust it just works.
(Except for this, that is: https://github.com/tokio-rs/tracing/issues/2519)
Opened the link. Saw my own comment. I'm still as confused today as I was then about how this was ever supposed to work—either the quoted code is wrong or there's some weird unstated interface contract. I gather from other issues the maintainers are uninterested in a semver break any time soon. Unsure if they'd accept a performance regression (even if it makes the thing actually work). So I feel stuck. In the meantime, I don't use per-layer filtering. That's a trap.
I've got a whole list of puzzling bugs in the tracing <-> opentelemetry <-> datadog linkage.