What basecamp did "represents a serious, collective, and repeated failure at Basecamp [...] counter to creating an inclusive workplace. Nobody should think that maintaining such a list is okay or sanctioned behavior here."[1]
Yes, and that's referred to a list of funny names. It's still not clear to me in what the "ground fact" (the list of funny names) is different from the links posted above.
I'll be frank- and I know that I'm risking the mistake of reading just what I want to read-, I think that those "counter to creating an inclusive workplace" and the general tone ("serious collective failure" etc.) are just nods to the social justice culture, and are meant to appease and concede some ground to the opponent. I don't think (also because it is clearly stated elsewhere in the same post) that there was anything intrinsically racist in that list, or anything that made it substantially different from those examples above. Apart from the obvious difference that these are customers, and it's not nice to secretly make fun of them.
[1] https://world.hey.com/dhh/let-it-all-out-78485e8e