Falling through a bed like in the article and then floating up and down like that just shows that the player and the bed are two separate entities. If the person is a human player, this could mean the coordinates of the player and the bed were the same at some point and then it'll move the player to noclip it. It doesn't show up like that for the player but only for others.

If the person is an AI, then it would first of all not make sense not to fuse them and second, it's highly likely either the bed or the character model has a boundary issue. This can cause boundaries to overlap briefly, but then they collide and since the character is a more dynamic model, it will continuously look for the boundaries of itself in relation to the bed.

In any event, these things are just general bugs that can happen in any game. It would seem GSC either doesn't test these things or they saw it, decided that fixing it would take up too much time and let it be.