There's quite a few things I noticed. Most you've mentioned, but I'll elaborate:
- It was definitely her vernacular in videos and interviews to start off with for me, though that's a bit more subtle to notice. It's hard to explain what I'm hearing if you don't know. But she talks and acts differently with black women and men - more than just a code switch.
- And then it was the music she plays. She literally always uses Hip-Hip or R&B songs in her stories, like, every time. She evens listens to stuff that I'm surprised a person like her would be playing without being fully into the culture. I always try to keep an ear out to see if she'll ever play any regular pop song, but she never does lol.
- Most dances or TikTok trends she does are ones from "black culture". All of the examples below

- Also, it's not much, but the fact that she's single and the way she talks about it makes me think that she's shy about the fact that she likes black guys as well. If it's not a black guy she wants, it's at least a light skin dude, I'm sure.
All speculation, but I'm glad I'm not the only one that sees it.