Well but he is neither the leader nor as influential as he is now. Deco and ronaldinho are generally did the more creative work.
Besides I stated that pirlo at his peak would've fit it into this barca system, not pirlo of now. There is a lot of difference.
“I haven’t changed…my skills haven’t declined. It’s just that football now is different. It’s played at a higher pace and it’s a lot more physical. The tactics are different now, you have to be a ball-winner, a tackler, like Patrick Vieira or Edgar Davids. If you can pass too, well, that’s a bonus. But the emphasis, as far as central midfielders are concerned, is all on defensive work…players like me have become extinct.”
This is what Guardiola stated before the time of his retirement and he acknowledged that Pirlo’s role was possible at Milan as they played ‘a different brand of football‘.
The reason I am siting above is, xavi's role is lot different under Guardiola compared to rijkard. In the middle of the decade passing midfielder role was almost non exist and xavi used to play as a link between edmilson and deco and he was not the guy on whom barca's play depended on. But that's not the case now, he performs a different role. He is never a level above deco in porto or pirlo in 03/04. He finally hit his peak in euro08 which is still going on and no signs of ending.
He may be a better player than deco or pirlo. But saying he is on a level above them for the last 6-7 years is far fetching and I don't think anyone who followed serieA or that porto team will agree. I guess you didn't watch 04 serieA when Milan won in a canter.
Edit: Xavi started on bench for barca in 06 final, so much for the theory of him being barca's heart for last 7 seasons.