Eh, ignoring a project isn't "absolutely horrendous", it's a little dickish at worst. They're free to accept or ignore any charity, and they're free to ignore requests for renewal. I don't know why they're not communicating (maybe they're trying to have less details publicly available for the inevitable post this would generate?) or why they'd be dropping this project entirely, but it's not like they're sending them cease & desist letters.
Many containers hosted by this project have the sole purpose of pirating media, so maybe it's not even Docker's choice to ignore the project. If they're being sued for providing piracy tools (and are smart enough to shut up about it until the lawyers clear them) it'd be stupid to explain what's going on and why. Last thing they'd need is for the copyright lawyers to make it seem like Docker is directly in kahoots with the piracy ecosystem. I'm not condemning piracy tools here, but everyone knows what you should expect if you're hosting piracy adjacent services.
It was pretty cool of them to offer DSOS to open source projects but I guess that's coming to an end if they don't even bother replying to their form anymore. But it's not like Docker is known to the public for giving other projects free hosting, the only reliable free hosting Docker provides are the containers they put under their own name spaces. It sucks people fall for the openwashing these large technology companies do, but I think people have unusually high expectations of Docker here.