Alright, let's accept the premise the OK symbol was originally just a 4Chan joke (and the implicit premise that 4Chan members, or the ones using "OK" as a joke, aren't racists*), and that racists just fell for it the same as anybody and began using it in earnest.

Does that really change anything about how we interpret it today? Besides being another example of "funny 4Chan hijinx", I mean. It's still used in earnest by racists, and I don't really care that much about the origin of any other phrase people use, so it's still worth doing a double take at anybody who smirks and throws up the OK symbol for photos.

*"racist" here means racist/alt-right/neo-Nazi/Proud Boy, which, this whole thread has been very insistent to point out, are all different things but share a lot of the same rhetoric and group identifiers.