I mean, maybe 'fun' is going a bit too far here, but the joy for the viewer is in how overreaching and frankly unnecessary this is. It's one thing to think that you could possibly kill 850 cyberdemons with revenant rockets, and in so doing achieve what the Doom community thought impossible: Nuts was never meant to be 'completed' like this. It's a whole other thing to work out how you could actually do it and then, tool-assisted or no, pull it off.