Hard to tell I think. I don't know enough about training, would it make sense for him to have a form buildup, that let's him peak just a bit before the Giro?
He's also supposed to not overly stress himself I guess, so we don't know how deep he dug, except for the TT, and even there he maybe could have cone faster at the start, he kind of indicated that (or it was just really good pacing, also possible ofc)
I think the important factor is how he looks compared to his rivals and I guess we can say, they look like he's toying with them.
There is no doubt that hes toying with his rivals and his form his very good. I am just looking at a larger Giro Tour double picture. Has he peaked? I dont think so. Time will tell how he fares in week 3 and at the Tour. Only against Skeletor he needs absolute peak (which may still not be enough), definitely not against Giro competition.
Obviously peaking before the Giro makes no sense but maybe at Liege they realized he is a bit too strong too early.