Everyone on earth can throw a punch. And Boxing skills whilst handy in a brawl are seldom deadly because they have to land first. Tyson could not have landed a punch on Lee if Lee had a straightjacket on.
Obviously anyone can throw a punch. Not many people can throw lethal combinations while protecting themselves and letting their opponents blows glance off the shoulders, if they land at all. Very few people could land the perfect left hook right under their opponents bottom rib (and that would stop anyone) - Tyson could do all these things. He was a skilled dedicated athlete, fast as **** and just as adept in his discipline as Lee was in his. Kung Fu has it's limitations too btw.
The pink power Ranger could kick any boxer's arse and Bruce Li was just an actor that used wires to float in mid air.