I'd rate Scholes over Pirlo, but not over Xavi. It is very difficult to compare these players, for sake of argument even if I agree that Scholes didn’t dominate top teams, question is, could Xavi and Pirlo do better job in Scholes shoes against? Remember unlike Xavi and Pirlo who always had two world class midfielders paired with them (such as Iniesta, Bouquets, Vidal, Seedorf, De Rossi, Guttuso), after Keane, Scholes never had player of that caliber to play along, and he always operated in midfield of two. As for replacing Xavi with Scholes in Spanish team, you could say United would not have had so much success under Fergie without Scholes, United’s decline coincides with Scholes too. I am not suggesting Scholes is better or even equal to Xavi but he certainly is closer to Xavi level than any other similar-style midfielder is.
Scholes didn’t struggle against top teams, a bit of a ridiculous suggestion. Case and point, Xavi and Iniesta played both legs against United in 2008 Champion’s League semi-final, it was Scholes’ goal that knocked them out of the tournament.
It wasn’t Scholes’ fault that United were not as dominant in Europe as Milan or Barcelona. United had a chance to do that after winning in ’99 but we screwed it up by failing to replace Schmeichel and Stam.