Hellgate's problems were more attributed to lack of central management and planning though. Most of the games ideas and systems were solid in principle, it just needed refinement and a real decision maker to iron things out. Plus I can respect Hellgate for at least doing something new, Diablo 3 really screwed the pooch on a golden formula that shouldn't have been difficult. Just even silly things that should have been obviously changed given the resources and time they had available, not to mention the experienced and superior management structure at Blizzard.
I get what you're saying, he took a cheap shot from a position of relative safety and there's some truth to that. On the other hand it has to sting a bit when people keep talking about how much they loved your old game but put out a poor imitation of it then actively resist the user base on fixing it (as they did for the first month). I can kinda see both sides of it.
Playing: Fallout 4, Warhammer Vermintide Watching: Into the Badlands, Ash vs Evil Dead