The simplest things become so damn difficult with their products.
You happened to hit the magic condition. It’s not simple. Macs have never been able to easily record their own sounds. It’s always been an uphill battle with installing special sound drivers and then configuring them for reliable operation.
Newer Macs also have security setting overlays and complications from other applications such as Skype, Zoom, and Meetings.
It can be something of a career move to get one of these to record itself and then play it back without the pathways getting lost. We should wait for someone with experience on newer machines.
It’s no picnic on Windows machines, either, but at least those machines have a history of built-in techniques and software.
I can try and sort out your drivers and sound managers, but it may take a while. I see you have more than one manager. What were you using Sound Siphon for? That seems to do what you want.
There’s nothing quite like juggling more than one manager. If you use Zoom, that’s four.
If you’re skilled in the use of the Mac System Preferences, that can provide little sound meters to help you in conditions where nothing seems to work right. Catch the sound half-way and see if it gets that far.
Looking. Does either Siphon or Blackhole have help?
. Sound Siphon 3 – App Audio Capture for Mac - Static Z Software
Sound Siphon makes it easy to capture your Mac’s audio. Use it to create virtual input audio devices that send audio from one app to another.