Considering you highlighted it when you quoted me, not sure if you missed the fact that I said I hated Lord of the Rings "as a kid"
I often relate to characters who differ from me and I don't always relate to characters who are the same gender, race, orientation as me. But I do tend to enjoy stories with characters that span a range of different genders and races over stories where all the characters are similar in those aspects. And I think it's important for kids to be able to see characters that share their traits fulfilling all kinds of roles. I don't consider diversity to be pandering but rather realistic in most stories where the character variation isn't limited due to some plot situation. Characters shouldn't have to be female or a poc due to "SJW" pandering, characters should be varied because humans as a species show a lot of variation.
Making a character a woman or a different race shouldn't excuse the writer from making them a developed character with a personality outside of that. In fact that's part of the problem when a cast has just one female character as being "the girl" often becomes her only personality trait since that is enough to make her different from the rest of the cast. Luckily this trend is fading away along with the trend of the token poc and token gay person... in large part due to media becoming more diverse and the novelty of a character being female, queer, or a poc no longer being seen as enough to make them interesting/different.
There are bad writers with diverse casts and bad writers with uniform casts. Those writers are going to make flat characters. I'm not saying making a flat character a woman or a person of color or lgbtq will save them from being flat. But if someone is a good writer who creates well developed characters but next to none of them are female or the female characters are not as developed or as interesting as the male characters, then that might be an issue and I would hope most of us could agree on that.