Which is stealing/paraphrasing Winston Churchill "yes I may be drunk. But my Dear in the morning I'll be sober and you'll still be ugly" or something close to that.
At the risk of dissecting the frog, the wit is in the assumptive twist about The Brown Bunny.
He was right, by the way: he did indeed get thin (he stopped being able to eat after losing his jaw to a surgical mishap), and Vincent Gallo is indeed still the director of The Brown Bunny.
To be pedantic, he lost a lot of weight before he lost his ability to eat. After his initial cancer diagnosis (and treatment), he went on the Pritikin diet and lost almost 90 pounds between the diet and weight loss from treatment.