Was Aaron Spelling overrated as a showrunner/TV executive producer?

From what I've gathered, Aaron Spelling never believed that ambitious writing was good for ratings. And he may have been right to a certain degree. His success proved him right. But his approach rarely helped a show long term. His shows got a lot of initial buzz. But when the novelty factor wore off, it became way too obvious that most of his shows (Charlie's Angels for instance) lacked substance.

And here of some anecdotes regarding his show managing come 90210:
http://teendramawhore.com/2010/01/17/beverly-hills-90210-producer-talks-college-years-slams-new-90210/

*Every pitch by the writers to Aaron Spelling had to start off with what Donna would be doing in the episode, even if she only had a few scenes.

*Jamie Walters' abusive boyfriend character was supposed to stick around and be rehabilitated. But Aaron Spelling had him canned because fans thought Donna looked dumb for staying with him. Jamie Walters still got paid a million dollars even though he wasn't on the show anymore.

*Aaron Spelling was always bad with casting minorities. That's how Mark Damon Espinoza was cast as Andrea's husband Jesse even though he wasn't very attractive. And the D'Shawn Hardell character was written out because Aaron Spelling didn't like that the writers were trying to put him with Donna.
https://www.reddit.com/r/BeverlyHills90210/comments/e2mb9d/the_lack_of_diversity_on_the_series_from_the/

*Jennie Garth hated Dalton James who played her boyfriend Mark in season 7, so Aaron Spelling told producers the guy was an anti-Semite and had to be fired. There was no evidence that was true, but the actor had been signed for a whole year and half the season had to be rewritten as a result.

*Aaron Spelling never wanted any of his showrunners to have success without him. After they left his shows, Spelling made sure that Fox never hired them again.