I’ve seen an attempted move from DD to OT and it was a nightmare of undocumented features and little compounded issues. Tracing was non functional. It doesn’t seem mature enough yet.
Because that's what happened.
I am a user of New Relic. Not because I'm happy. But because OpenTelemetry doesn't come close to the same features. Fortunately, at least OT is about 10x harder to set up with worse documentation.
Wait a minute...
New Relic is really really good too, so it was even more painful.
I agree it was a bit rapidly evolving in early days, but now its much more mature.
You can check out our docs for distributed tracing here - https://signoz.io/docs/instrumentation/
There are a lot of subtle issues, but we've been able to work through them to get usable traces. (Metrics and log ingestion already have pretty good existing open-source tooling, like statsd).
Incumbents in this space are in for a rough time as more applications provide meaningful telemetry, beyond just logs. Fortunately for them that timeline is 'fuzzy' at best.