Actually, according to the ADL website you listed, it seems it is not a hate sign...
The ADL goes on to say “the ok hand gesture” has several meanings in many different cultures...However, going back to the 1600s, it usually meant understanding, approval, or well-being...since the 1800s it became associated with the word “ok”...
The ADL website goes on to describe the whole white supremacy aspect, you are referring to, as a hoax that was started back in 2017...the ADL then states that in 2019 some white supremacists started joining in on the hoax to troll people...but to this day, the overwhelming majority of people use it as symbolizing approval...👌
https://www.adl.org/education/references/hate-symbols/okay-hand-gesture