His jab looked nice, but when I think of natural boxers I think of guys with explosive reflexes and/or pure power. So, I generally think of a technical, speed fighter like Roy Jones Jr. or Sugar Ray or I think of a heavy hitter who can just go in and blow the lid off of somebody like a schoolyard bully such as Marciano or Tyson.
If he doesn't have lightning fast hands in his boxing video or he isn't heavy handed and launching his weight into his punches such that they look devastating, I don't consider him a natural talent, and McGregor's hand speed is definitely below average for 154, and he doesn't know how to hit hard with boxing gloves because he throws from such weird angles, and not just the weird overhand hammers, but those loopy uppercuts too.