Why do you only mention "waitress"? From the upstream website "Built-in HTTP development server and support for paste, bjoern, gae, cherrypy or any other WSGI capable HTTP server."

$ grep "(ServerAdapter)" /usr/lib/python3.11/site-packages/bottle.py
class CGIServer(ServerAdapter):
class FlupFCGIServer(ServerAdapter):
class WSGIRefServer(ServerAdapter):
class CherryPyServer(ServerAdapter):
class CherootServer(ServerAdapter):
class WaitressServer(ServerAdapter):
class PasteServer(ServerAdapter):
class MeinheldServer(ServerAdapter):
class FapwsServer(ServerAdapter):
class TornadoServer(ServerAdapter):
class AppEngineServer(ServerAdapter):
class TwistedServer(ServerAdapter):
class DieselServer(ServerAdapter):
class GeventServer(ServerAdapter):
class GeventSocketIOServer(ServerAdapter):
class GunicornServer(ServerAdapter):
class EventletServer(ServerAdapter):
class RocketServer(ServerAdapter):
class BjoernServer(ServerAdapter):
class AutoServer(ServerAdapter):

Do you think all should be listed as optdepends?