> How would you represent metrics as traces?
Just instrument your meter implementation so each observation produces a span. Boom, free metric-derived traces.
Yup. Not a difficult problem to solve.
In the code define everything as a span with a name, scope (start-end), description and tags... and then you can easily dynamically produce traces, spans, logs or metrics based on what you need.
"free". The observability system would greatly exceed the workload being observed in many cases.