The only reasonable use case for asyncio is an API gateway or similar, when you issue a huge amount of HTTP requests, do very little CPU intensive tasks and waiting for I/O all the time.

Any other use-case you are better off going with the simplicity of a sync framework like Flask. For databases you are way worse with async, see why from the Python database god himself: https://techspot.zzzeek.org/2015/02/15/asynchronous-python-a...