I am not saying that this cat is a pessimist, I am saying he is a masochist. Whether it's the baby onesie or his sexual pose in a purple cat litter box, I think one can say that this cat likes to get down in ways that just aren't normal.
Note the convenient hole in the baby onesie that is for his tail, but also other purposes. The cone on his head serves as a portal for eroticism and sadness. Yes, this sad but purposeful cat knows what he is doing. Yes, when he said "It couldn't get worse," I am pretty sure he did want it to get worse.