According to the summary articles posted upthread, that seems to be what happened. The list was reinterpreted in the context of Stop Asian Hate to be racist. Which is not exactly fair given that the list is 10 years old. One should judge by the standards of the time, not the changing standards of today. And reading between the lines, that's essentially what the Basecamp founders said too: (paraphrasing) "this was a joke in bad taste made by people who aren't even at the company anymore. we're sorry that it happened, but it's water under the bridge." Then someone filed a racism complaint with HR against the founders and it escalated from there.