It's not really evident as after a couple of shots it turns into a brawl. I've trained with a couple of the UK's top bare knucklers a few years ago and the training they went through was ridiculous. Can't throw full power, have to pick shots as it's all about connecting clean & hard enough without hurting yourself
MMA would be bare knuckle if it wasn't for injuries, gloves were only introduced as a minimum as they found that a 4oz glove was the perfect size for reducing broken hands without sacrificing power, the gloves in MMA are to protect the fighters hands from breakages rather than the opponents.
That said, I'm not really a fan either. I do think there's a market out there for a promotion to do kickboxing or Muay Thai in a cage with smaller MMA style gloves.