I think the problem Luca Grease has is not that these decks are playing 4 colors but the fact that they're running a buttload of cards mainboard that are bad against combo and have almost no cards to bring in against those decks.
You could play 4c and be better against combo by playing more discard etc., rely more on Leovold to lock out the game fast vs. storm and griselbrand, it's not so much about the colors but about the sort of cards they run that make for man 35-65 matchups where with another deck building they could play a pile that's 50-50 against most.
Just take the most recent "4c-control" list on mtgtop8 I could find as an example:
http://www.mtgtop8.com/event?e=15412&d=293810&f=LE
This deck already runs 6 creatures (!) that you ideally want to board out vs. combo, not to speak of the 4 other cards that do nothing against combo g1, the 2 Kolaghan's Commands that are slow as hell and the bolt. Oh yeah, and as icing on the cake there's 3 planeswalkers, have fun getting those online when you rely heavily on keeping open countermagic vs. combo.
That's a total of up to 16 cards that I woud consider bad against combo. But what is in the sideboard? 4 more removal spells, a Loam in case things are not durdly enough and an additional Leovold because what this deck desperately needs seems to be card advantage. But hey look, there's a total of 8 cards against Storm and Show&Tell in the sideboard!
Am I tilted about this? Of course I am! I want to play matches as many matches as possible where every side has a decent chance of winning in a bo3 and that aren't determined by who plays which deck.