We use the Death’s Door rule in D&D, which lets PCs be unconscious instead of dead at 0 to -9 hp.
This lets the players take more risks, but the downside is that when a PC is unconscious, the player has nothing to do. Yesterday, two players were unconscious for most of the game, which sucked. If we hadn’t been using Death’s Door, their characters would be dead, but they’d be rolling up new characters and would be back in the game.
One way to mitigate the problem of extended unconsciousness is to provide lots of means of revival, but then that ends up being a form of insuring immortality.
I guess another way to address this is to always have less deadlier encounters. When encounters are always perfectly scaled, though, they become foregone conclusions and players end up realizing there’s no risk in engaging in every single one. Perfect fairness isn’t interesting when I’m playing, but I do think it is valuable to some.
That said, the risk should always be to the PCs, not to the players. There shouldn’t be a consideration that if an action is taken, a player will end up not being able to play.
So in the end, I have no conclusions, other than maybe Death’s Door is bad? It’s like paralysis, scaled up.