Manjaro replaced PulseAudio and JACK with PipeWire as default audio server in Jan 2024
PipeWire is described as a drop-in replacement for PulseAudio and JACK. not a direct replacement
PipeWire does not replace ALSA kernel API
Data from pactl list cards is what I would expect to see if the Monitor was plugged-in:
output:hdmi-stereo+input:analog-stereo: Digital Stereo (HDMI) Output + Analog Stereo Input (sinks: 1, sources: 1, priority: 5965, available: yes)
If the HDMI output is disconnected, the profile should change to available: no and the Active Profile should switch to another available profile, most likely the analog output and input:
output:analog-stereo+input:analog-stereo: Analog Stereo Duplex (sinks: 1, sources: 1, priority: 6565, available: yes)
If the Profile is not switching automatically, it can be changed manually in pavucontrol
Or
pactl set-card-profile alsa_card.pci-0000_00_1f.3 output:analog-stereo+input:analog-stereo