What's the point of early a2-a4 in the Modern Italian? It seems that just every top GM is now playing the modern interpretation of the Italian Game (with c3 and d3) with an early a2 to a4 Pawn move, something that only a few years back was considered a waste of time in the best of cases. The first "important" game with this idea is, if I am not wrong, the Carlsen - Karjakin game from 2016 World Championship. So what is the point of this early Pawn a2 to a4 move? Just gaining space on the queenside?
White obviously doesn't want to give light square bishop for knight. He can waste two moves with Bb3-c2, which is the old main line. Or he can just create escape on a2, after which Na5 doesn't make much sense. It gains space while it doesn't have to be so bad to exchange the bishop after Be6, if it didn't make additional moves.