Eufy (part of Anker) is the same. Our entryway is about 1/2" lower than the rest of the house. Small enough for it to fall in without triggering the edge sensor, too tall for it to get back out.

That's a good idea! Passive boundaries are better than active boundaries, for sure.

I have a Roborock (Xiaomi) S50 which just has a LiDAR on top and I can set boundaries based on an actual map of my house with the app. Greatly preferable over having to place random things around the house.

The newer/higher end Roomba’s with cameras on them have the same feature using VSLAM instead of LiDAR.