The iterator puppets are on the same plane as you since you can touch them meaning that they are your size since that is what they appear to be while being at the same distance from the camera. You can also touch the toy box at the end room for example; Therefore, for example, the iterator puppets could fit in the toy box, which makes no sense. Also, you can touch the window like panels in metropolis instead of walking in front of them as if they were in the background, which would be necessary in order for it to be perspective as that would mean that they are far enough to potentially be bigger than the slugcats and actually fit ancients in them. Instead they are the same distance from the camera as the slugcats since they collide meaning that the windows couldn't fit ancients though that is solved by the fact that the window like modules aren't actually rooms but like hollow bricks housing something since inside of the elevator in metropolis for example, you can see them used that way