I said this before, but what really makes people hate Jack isn't merely the fact that he is such a terrible person. It is the fact that he has received
so many different opportunities for success as well as second chances at life while being such a terrible person.
Jack has received so much that other people would kill for, and he has done absolutely nothing but make his life worse.
Strokes actually can impair your sense of smell and taste in a
number of different ways. Considering it was recently pointed he might have had an undiagnosed stroke back in 2009, it isn't out of the realm possibility he was dealing with the side effects before his YouTube career.
I would say another factor in his loss of taste is just how much crap he is consuming. Overconsumption of things like sugar especially will dull out your taste buds. I remember dieting once for quite a few weeks and then treating myself to a coke one night. It was one of the sweetest tasting things I have ever had.