Well in GL:TAS the love of his character's life died. Then in YJ, his own character died. Pretty miserable day to be a character voiced by Spisak. At least in GL: TAS they left the show with hope. While Wally is probably not dead, YJ ending was really quite a downer.
PS: Professionally it must suck for him too since he was voicing main character in two shows that got cancelled simultaneously.