Logging today does not support qualname. The reason was lack of support for co_qualname which introduced in Python 3.11.
I have a PR proposal to pass it through extras parameter.
It is not possible to change the Logger public interface without a breaking change, therefore putting it there is the least possible change.
The best non API breaking change solution is to provide a boolean per class and another per instance telling whether co_fun name or co_qualname should be used when func is specified in format string.