I see you didn't quote my full statement on why I felt Spock was a weak stand-in. Let me elaborate. Using a white actor to represent non-white people
First off, you're getting upset against a casting decision on a 50 year old show, a show that is generally lauded for diverse casting. Secondly, Leonard Nimoy, depending on your point of view, wasn't "white". He was Jewish, a historically oppressed minority (witness Patterns of Force).
that doesn't necessarily mean they can extend the same empathy
Should I not feel empathetic while watching Roots because I'm not black? Maybe I should only feel guilt instead? You have a sadly literal notion of identification and empathizing.
As for the flip side stuff, I think I see what you're saying but I put much stock in that mythological FOX News deck of cards.
You can't have a story without conflict. When the story takes sides for the viewer and doesn't allow any gray in the middle, that's when it gets too ham-fisted.