Post-edit TLDR;
such a good question I didn't really read your question specific to your situation. I think it's ok to learn a skill from kinda out-there people when there will be benefits, especially if they are good with not beating kids in the head with their bullshit. Also... forgot to mention the nerd factor, the biggest most obvious factor. As Joe Rogan says, you think it's gonna be a bunch of meat-heads at the jiujitsu school, but it's not. It's nerds. Nerd assassins. Nerds = Computers = 4chan = Qanon. So there's that.

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OK, so let's be honest here, there IS racial disparity in the BJJ world. Jiujitsu does not attract the amount of young black and brown athletes that other sports and martial arts attract, from boxing to even traditional martial arts. TLI had the first African American black belt champion ever, Jamil Hill, just last year (some of the best fighters of Brazilian history have been Black Brazilians though, see Terere, Jacare). It does attract people of all types from everywhere, to be sure, but there are several stigmas to this type of fighting (one: it's done on the ground, two: 'it's men hugging' etc) that give it a shade of being dishonorable, gay, ineffective, cheap, boring whatever, that doesn't rock well with young men's self-image.

There's also a class issue. It's expensive to participate in many places. Although there are more young men of color from the US getting into MMA and jiujitsu, the first wave of Americans picking up the sport from Brazilians in California were to a large extent white. Granted, many were the surfer types that may or may not be classified as liberal, but demographically, this was San Diego (not Southeast), this was Santa Cruz, not particularly diverse places. So already you're not seeing great diversity in it's base within the US, even though it's roots are typically left-leaning culturally, and I would argue, still is. Part of that I'll expound on later with the stoner factor.

So up next, the law enforcement factor. Just in terms of being able to perform their job better (giving the benefit of the doubt here), lots of cops sign up for jiujitsu classes. With the LE culture comes conservatism, right-wingery, Under-Armourism, NY-Postracy, and Giulianihilism, just off GP, but I have never been friendly to police officers (my wife's godbrother came after BJJ) UNTIL I started BJJ. I don't even get into politics with some guys because it's gonna end bad, but just as people and training partners I've come a long way in accepting other people's view points.

Then you have the UFC factor. These are the guys that 'trane UFC, bro'. Now, I love MMA, but I don't love all of its fans. It's kinda self explanatory what kind of bigoted, nationalist (domestic and abroad), mf's might also love the sport. Mix that with a gym that promotes toxic masculinity and you've got problems.

Lastly, the stoner factor, which when conflated with the woke factor, can lead to a rush to know more about the unseen, to understand the universe more deeply, than your more mainstream brethren. This is the corner of the BJJ universe where the Eddie Bravos of the world congregate. In order to avoid this, just don't let them do 10th Planet jiujitsu, is all. In fact, they shouldn't even do any nogi until they complete a year of training in the gi.