The point is that beauty is subjective.
How the Okama are depicted is how the world sees them. Abominations of nature that should not exist. Monsters and demons and everything gross.
But they don't see themselves that way. Ivankov see a group of the most gorgeous people in the world. Litterally candy.
By illustrating them in this caricature way you can best convey the strength of their existence and give readers a legitimate, not just shallow, reason to love them. What they wear is a form of armor to protect themselves. Even though they are hated they have chosen to love themselves and found a happiness that can not be taken by others, which is a pain they likely know well.
And in a way they have conquored beauty, which was a dream that was supposed to be impossible for them. Things are not either beautiful or ugly. Beauty and beast exist in all things and the difference between people is whether or not they can see it.
So if you see the Okama and can't get past the knee jerk of 'Ew!' you've genuinely missed the plot and understand beauty the wrong way.
it really does continues to fascinate me how oda has the absolute worst physical artistic portrayal of trans people i’ve ever seen but continually utilizes them story wise with like a very good understanding of queerness and pride like how did that happen