It’s like short women who only want a tall partner because they feel insecure and need to compensate.

My ex is short, five feet tall. First she married me, I'm 6'1". The guy she married after me is 6'5". She's not an insecure person at all, just prefers her men to be large, for, umm, reasons. I'm guessing husband 2 is larger in many ways than I am, given that he wears size 15 shoes and can easily palm a basketball. Regardless, they're obviously happy with each other, as I am with my current wife, who's of average height.

Size differences between partners can also be driven by insecurity in the larger one. That's not true in my case, since I've enjoyed partners of widely differing heights, a couple of them even taller than me. But I've seen plenty of that with (for example) weebs. And of course there's the myth that Asian women (south or east) are docile and servile. That has not been my experience at all. But I prefer women with strong personalities, so it might be a self-selected sample.

But here it’s a woman who feels that her non-whiteness is inferior

There's plenty of tone-consiousness embedded in Indian culture, and there's also the colonial cringe in many cases: the notion that those who resemble the former imperial masters are of higher status than the locals.

I suspect in the Vance case that he presented himself in one way before they got married, then did a sociopathic pivot afterward. And for whatever reason, Usha has kept quiet about it. It's very hard to tell what goes on inside other people's relationships.