LOL. I may never stop laughing at this. If you're suggesting that Durant or Curry are better all-around basketball players than LBJ then you need to watch a lot more basketball.
If we're only talking about shooting, then LeBron (while far better than average) is the worst of the three guys you mentioned. In every other facet of the game (rebounding, passing, playing as part of a team, overall offensive efficiency, individual defending, and team defending), LBJ is far superior to the other two. Furthermore, I would argue that LBJ's basketball IQ is the highest of the three. He almost always makes the right play.
Never in the history of the NBA has there been a player with LBJ's offensive skillset who defends at the level he does. Ever. There have been better offensive players and better defensive players, but no one has ever been as complete a package as LBJ is right now. And LBJ is probably the most versatile defender the NBA has ever seen, as he can legitimately guard all five positions. That's because of his combination of freakish athleticism and genius-level basketball IQ. If you want to hold his freakish athleticism against him, that's your prerogative --- but it doesn't make any sense at all.
This would be a different discussion if the intent was to identify players that maximize their output relative to their physical talents. Not because LeBron doesn't do that well, but because his baseline (based on athleticism) is higher than any other NBA player's. A guy like Steve Nash, however, is not an elite athlete but he became an elite player anyway because he processes the game at a speed that most people cannot. If that's the context, LBJ may be overrated --- but that's the only context in which I believe he's overrated. It's pretty tough to overrate the greatest all-around basketball player of all time ...
-HooDooKoo
