The changes for season 2 were hated by fans at the time, and the show certainly lost some of its sciency sophistication (not that it ever had a lot). But what I think people forget is that Fred Freiberger was a guy who knew what TV audiences wanted, and how to give it to them; the alternative to letting him have his way was not “season 2 like season 1” but “no season 2 at all”. He was the guy the network put in when they really wanted to cancel the show and were already slashing budgets and changing schedules (see also Star Trek season 3), but needed to make it look as if they were giving it a chance.
I’m sure I’d have disliked him personally if we’d ever met, because I don’t get on with extroverted TV people. But a lot of fans seem to think of him as the Guy Who Ruined Then Killed Their Show, where I think one could make a better case for his being The Guy Who Gave It The Best Chance It Could Get.