Ok so I can see how this will account for some of the confusion, but certainly not all of it. When I first got my phone I experimented with different chargers (usb-c, MagSafe) to find a setup I liked. I concede that my phone may have displayed the wrong StandBy clock in the same location, due to different chargers being used.
However, just yesterday (as one example) I had my phone sitting on my MagSafe charger at my girlfriend’s house in the late afternoon. I have been using this charger at this location for a few days. I noticed that my preferred clock was displayed (I remember this because I noted the bright colorful numerals that I rarely see in my own apartment, where my bedroom is regularly too dim to show anything but the red Night Mode numerals). Then when going to sleep I dropped my phone on my charger and the Photos module was selected. I swiped over to the clock module and some random, lame digital clock that I have never intentionally selected was displayed. So I swiped vertically to select my preferred clock.
Apple needs to expand the StandBy preferences in Settings to include a Default clock choice. I’d also like to ability to enable always on display only in certain focus modes, or only when plugged in. But that’s a different conversation.
One other inconsistency I’ve noticed: I connect my charger (MagSafe or usb-c) and set my phone down horizontally. I’ve oriented my phone so the power button is facing up. I press the power button and StandBy is enabled. But 2-3 seconds later StandBy cancels and I see my horizontal Lock Screen instead. This happens not frequently.