> Distributed tracing is also only beneficial if you have the associated logs - so that you can understand what each piece of the system was doing for a single unit of work.

Ehhh, that's only if you view tracing as "the thing that tells me that service A talks to service B". Spans in a trace are just structured logs. They are your application logging vehicle, especially if you don't have a legacy of good in-app instrumentation via logs.

But even then the worlds are blurring a bit. OTel logs burn in a span and trace ID, and depending on the backend that correlated log may well just be treated as if it's a part of the trace.