No, not in my group.
On the rare occasion that the players in my group have decided to take someone prisoner, I'm not going to demotivate them by allowing a chance that the KO'ed prisoner wakes up and makes life difficult for them. My players are plenty murderous enough already. If an NPC is KO'ed, it stays down for 1d4+1 hours.
Conversely, if (as DM) I choose to have an NPC knock out a PC, it's clearly for story reasons. In this case, I don't want to leave the story in the hands of the d20. The PC is out cold. They're not at risk of dying (and they know that, which is a good thing), but nor can they hope to pop back up and influence the fight unless they get magical healing.
Bear in mind that, in my group, a knock-out attempt might occur once every 4-6 sessions (i.e. every 20-or-so combat encounters). My group's motto is: kill them all, and let the gods sort them out. In the last month alone, they've killed multiple innocents: chucked a fireball into a room where cultists were about to sacrifice a prisoner (killing the bound prisoner), shot an unconscious slave in the back ("Body face-down at the bottom of a pit? I'll put a bolt into his back, just in case he's a zombie or something"), killed the entire population of a town after accidentally detonating an orb of destruction, and murdered a friendly NPC because they detected magic items in his house. If anything, I need to be figuring out more ways to incentivize them to not kill everything in their path.
So, yeah. No way am I ever going to give them another reason to simply kill the NPCs.