Holy fuck, are you not paying attention? It does not matter if it was sudden or not. If it got to the point that the DM was willing to twist the narrative to kill the entire party, they should have already left.

I haven’t been traumatised. Heck, I’ve barely ever been a player. I just don’t know why people are being so defensive of vindictive DMing. It’s deeply unhealthy. Doms do need aftercare, but they also shouldn’t go into their fun with spite on their mind.

Your example is NOT an example, because that player was not murderhoboing. You weren’t vindictively adding an element to the game to get him killed, you were organically reacting to their actions with details that had already been established. Your consequence made sense, and it made the game more fun for everyone involved.

It is a DM’s job to make sure everyone had fun at the end of the session, DM included. Technically, that’s everyone’s job, but the DM is the one with more authority. This doesn’t mean bad things can’t happen, but nobody should be outright miserable. If one person’s fun would detract from someone else’s fun, then either a frank conversation is needed or someone should leave to find that fun elsewhere.