The DOJ filed a lawsuit on behalf of the EPA against eBay in 2023, seeking to hold them liable for prohibited pesticides and chemicals as well as illegal emissions control cheat devices sold through the platform that violate multiple federal laws and environmental regulations.
There wasn't even really an argument about whether or not the items were actually illegal to sell - all parties including eBay basically stipulated to that and the judge even explicitly acknowledged it in her ruling - the entire case came down to whether or not eBay could be held liable for the actions of third party sellers on their platform who they failed to proactively prevent from selling illegal items.
In September 2024, U.S. District Judge Orelia Merchant granted eBay's motion to dismiss the case, ruling that Section 230 of the Communications Decency Act of 1996 provides eBay immunity for the actions of those third party sellers.
DOJ filed an appeal on December 1st so we'll see where that goes but as it stands now - no, you couldn't take eBay down even by listing stuff eBay does know to be illegal, based on current precedent.
Why the courts applied Sec230 that way in one instance and not another is the real question and the more cynically minded might also wonder how eBay founder Pierre Omidyar's various philanthropic and political endeavors (including but not limited to being the $ behind Lina Khan's whole "hipster antitrust" movement) could be a factor too. He's no longer an active board member but still a major shareholder whose existing shares would likely be worth a lot less if a case with a potential ~$2 Billion in fines had been allowed to proceed.