In 2014, America's Top Model featured a contestant with vitiligo, Winnie Harlow. She was popular on tumblr, popularizing the skin condition.
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You may notice that she's otherwise a thin, conventionally attractive woman, and that her vitiligo is strangely symmetrical, making it look more like a full body tattoo, while tumblr usually drew obese hairy lesbians in hijab. This is just a classic case of the echo chamber of tumblr's "I'm more body positive than you!" arguments.
Then, porn got banned on tumblr, causing a massive exodus of tumblr users to twitter. Twitter had long been popular with media personalities, meaning that ideas that got popular on twitter would find traction in mainstream entertainment. So you have a Norwegian game studio with Trump Derangement Syndrome designing characters indirectly inspired by American teenage girls making fanart of a reality show about models.
TL;DR: Because Tumblr/Twitter.