"Get rid of the entire cast" as an excuse for getting rid of Majel? I think NBC simply did not like the casting in general.
No, that isn't what I said. I meant that they used "audiences didn't react well to a female first officer" - while probably true based on the historical record - as an excuse for getting rid of Majel, because they found her acting lacking and weren't keen on casting the producer's mistress in so prominent a role in the first place. In other words, it was a combination of reasons. I didn't opine on the "entire cast" at all - just Majel.