I was thinking about this last night. They should just run it exploitable. Basically if they relaunch they will get hacked immediately because the source code was shared and is really old. Patching it in the time needed for a reasonable relaunch isn't possible.

But if your site is dead then you might as well go for a hail marry. 4chan is supposed to be a giant edgy game. So turn it into the most hackable site. Better than no site. Sometimes you have to take the bad with good stride to save face.

Just put up a notice: Yes we know we will get hacked. We don't necessarily welcome it but we know it will happen. We could even make this fun. If you do hack us all we ask is that you do something fun instead of harmful once you get it. In fact we will not pursue any criminal charges against someone who hacks us and doesn't cause serious damage.

Bam! Now you have a site that people will go to just to see the lastest hack. And you've set up a cat and mouse game where you can improve your source code seeing real attacks. With the license to hack the site tons of security researchers that want responsible reputation will hack you and tell you how to fix it almost as fast as real attackers.

Is it a good idea? Maybe not. But it has a shot at working while just killing a website doesn't.