The specification defines IdGenerator as an extension point:

https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/sdk.md#id-generators

The yaml for tracer_provider: should probably allow to define which id generator to use, something like:

tracer_provider: id_generator: # SDK extension point my_custom_id_generator: 

Found while prototyping for opentelemetry-cpp