On the one hand, Fish is a jerk. A lot of the harshness he received, he brought on himself. He conducted himself in a manner that showed he thought he was God's gift to video games, while also showing him to be very naïve. He is a talented game designer, certainly, but he needed a figurative kick in the pants to take him down a few pegs -- and, who knows, maybe if his detractors hadn't gone overboard, he might've learned something. I'm disappointed he decided to stop being a game designer, rather than stop being an ass, but really, I'm not surprised, either.
On the other hand, threats of physical violence are way beyond anything he deserved. Hearing about people doing that over stuff like this always saddens me -- that there could be some massive failing (of society? rearing? education?) in so many people's development that led to them being so uncivil. It's massively immature at best, and dangerously unhinged at worst. And it's such an alarmingly vocal minority in the gaming community, too.
I'll join the chorus saying I'm also a Jimquisition convert; early on, you said a lot of things I agreed with, but you just seemed so incredibly unlikable. It wasn't until I saw you at Escapist Expo, so very different from the persona you project in your videos, that my opinion of you started to change. I gave your show another chance, and I liked it. Your harsh and arrogant tone had become a jest, you'd turned around on several points that had colored my initial opinions of you, and you became better at your craft, too. It's sad to know now that you'd considered quitting, but I'm glad you instead made the choice to improve.
Phil Fish could learn from your example.
[EDIT] Sometimes wish this forum had upvotes. j-e-f-f-e-r-s came along and posted while I was writing mine, and said very well a lot of the same things I did, but with a lot more precision. Thumbs up to that post.