Why grandmasters play giuoco pianissimo less often than the ruy lopez? White players in search for the win are sometimes annoyed when people play the berlin defense against their ruy lopez. I notice that the italian game often reaches position very similar to the ruy lopez middle game. So my question is why grandmaster do not switch to the italian game as the new E4 main line?
In italian game black put his bishop easily to c5 while not making too many concessions. In Ruy-Lopez prospects of that piece are usually worse. Berlin is not the main choice for black in the first place and it isn't horrible to play with white either. Many black players just stop thinking about Berlin the first time they see Re1 line. No fun at all. Endgame, while interesting, also not to everyone's taste. And white can settle for d3 systems. Black positions seem perfect by machine eyes, but still people prefer a6. The more people play a6, the less you worry about Berlin. And you can still make your opponent suffer in Berlin.