It's just a "clever" rhetorical trick of considering rules and real world physics only where it enables them to pull bulshit.

To be fair, it's pretty funny but I would never let that fly in a regular game.

Yeah. I'm usually not one to accept "The DM can fix it" as an excuse for bad rules, but it absolutely applies here. It's an extremely specific set of circumstances that can only happen if the players are trying to break the game and the DM lets them. It's not a broken rule in practice so much as it is a fun thought experiment for people to talk about.

I think there are much better examples of broken rules out there.

That is not true. You are ignoring half the written rules for this to work.