I agree with the general direction of the post. Even though diversity is a nice thing, writing will always the reflect the writer.
It’s the “Write what you know” paradigm.
Geeks write geek fiction, funny people write the best humorous fiction etc. It’s the reason why in US sci-fi is American centric and Japanese Anime is Japan-centric.
On that point though, cognisance must be taken of the fact that Japanese Anime, for a country which is clearly less diverse, represents significant character diversity when compared to Western Cartoons (including black and european characters).
It IS true that even for western SFF that is set on a global scale, global representation can be extremely skewed for no good reason.
As a teen I was irritated by Julian May’s Galactic Mileu – So many world cultures and yet the cultural identities with the strongest Psychics (Irish, Polish and French/Franco-American) were all caucasian! Tell me that isn’t skewed.
I think for diverse writing, what we need to look towards is diverse authors and artistic freedom during formative years.
Stereotyping is real and it does affect the type of fiction a budding writer is pushed towards writing. As an African writer I am continually given subtle pressure to write something ‘real’ and political after the nature of great African writers.
Freedom of expression and growth needs to apply to authors as well – even to the extent of crossing over or colouring our work with other genres.
Diversity in writing isn’t an ailment in itself, it’s merely a symptom of a larger social shortcoming.