Ebay has had an "offensive material" policy since at latest 2018 -- that's the earliest that Wayback Machine has a capture of the URL that the present "offensive material" policy is at.
The 2018 one probibits "items that promote or glorify hatred, violence, racial, sexual or religious intolerance, or promote organizations with such views"
I am not sure to what extent or in what ways it has been enforced against what sorts of items. Perhaps it has been enforced unevenly or mostly not? I suspect that nazi memorabilia, at least, has been consistently rejected for a while.
But the policy is not new.
The today one at that URL gets into a lot more specific details than the 2018 one, including prohibiting "Items with racist, anti-Semitic, or otherwise demeaning portrayals, for example through caricatures or other exaggerated features, including figurines, cartoons, housewares, historical advertisements, and golliwogs"
It looks like those details were there as early as Nov 2020, not sure how long before that. But that predates the current Seuss controversy.
