I guess it depends on whether those in charge want those cast members back. To some in the higher offices, budget and spending is the ultimate concern, not story flexibility or even viewer enjoyment. Having someone at the show level who can make all the unpopular choices (hirings/firings, department cuts, etc.) but keep the budget in check would be very popular in the higher-level offices, since it averts blame from them. If the viewers demand this slate of old favorites back, it throws a wrench into the higher-ups budgetary constraints, especially if they also lose their top cost-cutter/"hatchet man" in the deal. This EP's shenanigans certainly rises to the level of being fired, but they would only fire him very reluctantly, since he was doing the tasks they needed done WRT their budgetary demands. He just went about in a horribly unprofessional way. Deciding to fire him is easy, but getting someone else in to do the same tasks he did (in a nicer way) might not be possible without losing a lot of ground in keeping the budget in check.
For contrast, GH's Frank Valentini gets a lot of good press for his ability to deliver his show to ABC at or under budget every year, and yet gets equally good press for how the cast and crew like working for/with him. The actors especially seem to rally around him by including him in press events, fan convention panels, and the like. So while such financial "realities" mean a lot of sacrifices and likely a lot of hurt feelings, it is possible to be professional and respectful about it.
