Getting back to the OP. I can actually see the correlation with the sex and gender debate in the following way:
Both gender believers and (in this case) the black men on stage are relying on external factors to keep them comfortable.
Trans people want validation from society that they are what they say they are.
And POC clearly do not want to hear racist slurs hurled in their direction.
I think rationality has to come into play here, in both scenarios.
Transpeople will have to acknowledge that many people will not see them as they are.
And these men (in this situation) will have to acknowledge that the slur was unintended and caused by a disability.
I truly hope John Davidson is alright. I don't know much about him but he must be feeling even worse than ever with all this hoohaa, after what should have been an amazing night for him.
In both the above scenarios I think it's useful to think about who you would rather be on each side of the debate.
Trans rely on lies to be happy, gender criticals have the truth.
JD lives with a truly life limiting disability every day over which he has no control. The men on stage have a choice as to whether or not to make a big deal of it, it's just one moment in their lives (albeit a significant one).
Obviously intentional racism should be challenged and I think that's where everyone's outrage should be focused.
I hope I've worded this correctly.