Not sure I understand what you need but I’ll try to address each of your lines as best I can:
What is this a list of?
I guess you want to know whether the list is connected to a collection. The answer is yes. If it were not connected it would not have displayed the first item in the collection’s only record.
No filters applied. The list is set to Show All record items.
No sorting applied. That’s perhaps why it seems to start with the first item in the record. I have provided an image of the record.
No maximums set. there are only eight datums in the record (excluding the ID)
No permission restrictions. If there were the list would not display anything. not even the single datum.
Mine is not a custom list. I deliberately chose the simple list. I have been troubleshooting this issue and I am wondering whether removing some of the default display items would have anything to do with it. I removed the left side (avatar) and the subtitle elements, and added a selection toggle button on the right. I then applied the ‘To List’ action to it.
They are properties. So in the list you have added the first property from the magic text only. Now you can add other properties with magic text. If you need to show these all properties I suggest to use a custom list because in a simple list all values will show in a single line with dots when the data count exceeds.