White supremacists use it in a slightly different configuration. Flat armed, palm upward. They’ve evolved it pretty specifically.
It’s also never used by a normal old person in any context other than an explicit “OK” scenario, so almost any other context of use (or lack thereof) is suspect.
Its old use isn’t even a common gesture in the US anymore: most people use the thumb up gesture instead.
Most importantly, I’m more than willing to be wrong. If someone has red flags, I cut them out. That gesture is toxic, and anyone who makes it is at best ignorant of the current political climate (which itself is a red flag).
I treat it the same way I treat certain 8chan/nazi/alt-right/incel/mra shibboleths. If someone uses them, the best case scenario is that they hang out a lot with actual people of those types, which is a giant red flag.