Comment 6 for bug 1838577

I think you're right. I'm just assuming that 'module-switch-on-connect' is a little dumb and can't tell the difference between a fresh boot and hotplugging. If that's an issue you want to discuss then it would probably be best to open a new issue with the upstream developers at:

  https://gitlab.freedesktop.org/groups/pulseaudio/-/issues