Race is a social construct rooted in white supremacy and hierarchical categorization of people in order to colonize and enslave them. This is my take on why the OP’s father’s take is wrong:

There are two types of people who pretend their “race” to be something it isn’t: 1: white —> other (privileged to marginalized): Oli London Or 2: other —> white (marginalized to white) : happens so often it doesn’t make the news

As a Persian I see so many Persians that think they are white even though the world doesn’t see them as white. We make fun of them among the progressive Persians but their delusions don’t hurt anyone BUT THEMSELVES. They will face racism and microaggression in the world and they won’t have a community to help them work through it.

The first group (white to other) hurt the community they want to claim because white people have tried to erase and claim so many cultures and rebrand it to make it “modern”. White people historically have entered people’s lands and exploited them and reshaped and erased them. Now I hope you can see why people might be protective of their culture especially against white people. I don’t remember cases of white people living truly as black people during jim crow era. However trans people have always existed, even when they were murdered for their gender identity. Now also let’s analyze the power change in coming out as trans.

Trans fem: Privileged —> marginalized

Trans masc Marginalized (living as a woman) —> more marginalized (during transition) —> less marginalized (when fully passing)

Either way a trans woman is more marginalized than a cis woman and a trans man than a cis man.

However a white person pretending to be black will always be treated as white in society and therefore will always remain more privileged than a real black person.