While the usage of the ok sign likely began as a LARP hoax, it has since become adopted as a high sign/shibboleth by actual white supremacists and adjacent fringe groups like Boogaloo Boys, similarly to Hawaiian shirts.

That’s the entire point of these types of signaling behaviors - they’re plausibly deniable, innocuous or not obviously offensive or aggressive, and they’re usually inscrutable or indecipherable to the out-group while being effective as signifiers of the in-group.

I hear that a lot.