I don't see the point in piling on Gene. He's been dead for almost 25 years now. All the behind the scenes shenanigans are well known. Harlan Ellison has been bitching about it since at least 1970.

Fred Frieberger probably had the best of intentions, but he managed to sink not one but two cult SF series. His Trek association got him welcomed aboard Space: 1999 in it's second and final year, and the drop in quality was comparable to the third season of TOS. That's a hard thing to live down in the eyes of fans.

The legend goes that Spock's Brain was written as a joke, only Fred thought it would make a good episode.