HDMI audio output is not switched on/off automatically
With PulseAudio, plugging in a TV or projector to the HDMI port would also switch the default sink from the internal speakers to the HDMI, and unplugging would switch the default sink to the speakers (as well as rescue all the streams).
None of that happens with PipeWire: when something is plugged into the HDMI, sound continues going to the internal speakers. If I switch to HDMI from gnome-control-center, later when I unplug sound continues being routed to a non-existing HDMI output.
Internal audio: Intel Corporation Cannon Lake PCH cAVS (rev 10)
Graphic cards: Intel Corporation CoffeeLake-H GT2 [UHD Graphics 630] (rev 02) + NVIDIA Corporation TU117M [GeForce GTX 1650 Mobile / Max-Q]
(Not sure which card the HDMI is wired to)