I personally think don't think Messi will have as good of a legacy as people think now - The guy is only 26/27 and if there is a decline and doesn't retire until he's 35/36 people will remember this deteriorating player more so than what he was in his prime, Giggs was a victim of this.
Messi's 4 Ballon d'or's aswell, 2 of those he shouldn't have won, 1 occasion even saying that himself. There is a lot of love of him within FIFA and football in general and he gets votes/awards just on shear merit and that's what annoys some people (certainly me), hence him winning the World Cups best player - Everyone knows he wasn't, but it will be one of those in 3 years time, where you go
"Messi had a shite World Cup 2014" and you'll get some people going
"shite World Cup, yet player of the tournament "
And that's what Messi is to me I'm afraid, a pretender great in comparison Maradona/Pele due to peoples love of him and giving him votes/awards on shear merit when he realty should be nowhere near their legacy.