The name is dumb. The rule isn't.How can some people still seriously consider a variant called "gritty realism" in a game like D&D where everyone fights at 100% full strength until they are unconscious is totally beyond me, and that's the tip of the iceberg. There is nothing "realistic" in D&D anyway. Just tailor your rest for the level of action that you feel is right in your campaign and with the style of play of your players, but linking this to "realism" is simply absurd.
The name is dumb. The rule isn't.