The ok hand sign can be a perfectly innocuous hand sign in some circumstances, or a white supremacist dog whistle in others. The very purpose why it was adopted by white supremacists is this confusion - this has been explicitly researched by human rights groups.

Of course, the symbol itself carries no white supremacist overtones, just like the swastika in itself does not carry any nazi symbolism (as opposed to, say, a crosssed out star of David, which would be an explicitly anti-semite symbol). However, it's association with and repeated use by Nazi Germany is what gave it a nazi symbolism. Even for such a widely reviled symbol, there are still non-taboo uses. In particular, a left-facing swastika (sauwastika) is a common Buddhist symbol, found often in Asian media with no Nazi connotation. That means that a bald person waving a swastika flag could either be a nazi skin head, or a buddhist monk - context will usually tell you which.

This is similar to "states rights" rhetoric - it has both its literal sense, the discussion of the amount of power states should have vs the federal government; but it also refers more specifically to the "right" to slavery the civil war was fought over. When you hear someone speak about it, you need more context to know which sense is being used.

Human language is complicated like this.