The main difference I see is that, at least in my case, the A/V gear will be off when I'm not actively using it, i.e., sitting in front of it.
My network gear runs 24/7, even if I'm away from home for multiple days at a time. I usually only turn it off when I leave for longer (>1 week) holidays.
If it has a working remote control or a soft start power switch its never "off".
Most cheap hardware does not have X or Y safety class capacitors so if there's any exposed conductor you're probably marginally safer on an insulator like wood.
I'd expect most components to fail under stress which is not the case in a low-power standby mode where only a single 5V power rail is active and sources a few milliamps.
Not great and I personally wouldn't put equipment in cabinets, but I'd expect most failures to occur when the equipment is actively being used & under stress, not during standby.
There is a self heating failure mode for capacitors that would depend a little bit on current drawn, but the voltage across a cap would be constant regardless of current drawn so safety and fire related failures are primary based on time.
"Name Brand" products with legitimate UL listings almost entirely use Class X or Y caps where safety regulations require them and would be immune to this problem due to internal construction differences. "No name gray market off aliexpress" would be an unwise choice.
It's surprising how few fires we have from household electronics. The odds are it'll be fine.
My network gear runs 24/7, even if I'm away from home for multiple days at a time. I usually only turn it off when I leave for longer (>1 week) holidays.