Seems like they’re getting too hung up on doorways and not noting that each room is a separate environment cut off from everything else by the four walls. It cuts you off from all previous visual points of reference. When you move around in one room, your view of the same objects shows you you’re still in the same place, even if seeing it from a different angle. Going into a new room cuts you off from all previous points of reference.

They need to test 2 adjacent rooms divided by a large open archway that allows one to see most of the adjacent room. I suspect the visual continuity when moving between spaces would not impact memory as much.

One could also test walking down a city street to see what effect a changing but continuous environment has. Constant new environs, but transitioned continuously from one area to the next.

The reason I’m skeptical is that human brains predate doors.