Okay, let me try this 'critical thinking' thing you speak of:
I assume you're not accusing @ratscout of defending -isms in her actual post in this thread, but rather you're saying the sentence "I wish we could have a civil conversation without immediately resorting to calling each other racists/sexists/and other ists" suggests that when she hears people accusing each other of -isms, she assumes the accuser is being oversensitive rather than the accusee actually being guilty of -ism?
I assume you were referring to the part where she said "A very small percentage of the population is gay, and you might have trouble marketing it to the other, like, 99% of the population if you are trying to solely sell the show on that."?
I read that as a colloquialism (i.e. "the majority of people aren't gay"), rather than a statement of fact (i.e. "literally 99% of the population isn't gay"). But then again, I'm not gay, so I guess it's easy for me to read it that way 
I can see why @ratscout's post reads like 'marginalized communities aren't allowed to market their media to others based on the sexuality/race/etc they personally identify with', just like I can see why @ratscout felt like people are implicitly accusing each other of -isms in this thread.
To me, she was making a pragmatic argument against diversity marketing (i.e. 'it's not in your best interests to do so'), which is very different from a moral argument against it (i.e. 'it's wrong of you to do so and makes you 'woke' or something'). She might be wrong about diversity marketing not being a pragmatic move, but we should focus on that instead of acting like she's making a moral argument when she's not :]
(And of course, if I'm incorrect about what your points were actually trying to address, I'm happy to be corrected if you want to do that
)
(EDIT: Don't worry, your responses are working (in the sense that Tapas notified me) - I think it just doesn't show up in the thread when it's the next comment in the thread for some reason XD I have been bamboozled by it too :'D)