I'm not sure I follow your point here. Is your argument that he's not so great because some of the world's best players don't try hard enough against him? Every time? If you watch enough barca you'll see that plenty of teams try to kick him and either can't get near enough to do it, or he rides the challenge and carries on. Look at that nutmeg he did on Milner the other night just as he was sliding in with a full blooded challenge. Just flicked it through his legs like he wasn't even there. There's no need to be cynical. Just enjoy watching a genius play the game.
Anyway. Personally I don't like trying to classify one player as 'the best.'
All I know is that when I watch Messi play, more often than not its like watching a magician rather than a sportsman.
The guy has unbelievable natural talent. Ronaldo is also a physical phenomenon and is 'better' at certain things. But messi isn't nearly as much as a physical specimen but still manages to be incredible.
He's also one of the few barca players that tries to stay on his feet despite getting fouled all the time.