I'm pretty sure 4chan is talking to the feds right now and are likely collecting evidence. 4chan will most likely come back online and give out an announcement in regards to this, probably in a few days from now.
So what lessons can be learned from this?
It seems those Sharty hackers aren't the sharpest tools in the shed because if you are going to commit a crime like doing a data breach, under no circumstances should you openly admit to any crimes on the Internet publicly (especially if you want to keep your freedom because the hills have eyes, the feds are always watching for people that proudly self-snitch on themselves). In this case the Sharty hackers, they were posting soyjak memes and openly saying "Total Sharty Victory!" like they do with a lot of their victims. This is not really a smart move, especially since they committed a data breach on a major online community. Those hackers are smart enough to exploit a vulnerability but the hackers in question were stupid enough to show their affiliation with the Sharty. Since the culprits were posting Sharty memes, they self-snitched on themselves should a federal investigation come from this because we no longer have to guess who the culprits are (this is how the feds busted the people that were part of infamous cybercrime groups like Lizard Squad and LulzSec because some of the participants in those communities talked too much online).
If you are going to commit cybercrime, avoid self-snitching on yourself (shut the fuck up and the feds will have a much harder time finding you should you choose to commit online crime).
4chan is also at fault for not doing a good job at keeping their shit secure. It seems 4chan hasn't updated their back end since 2016 so had they done so then 4chan would've taken advantage of cybersecurity patches to prevent or at least mitigate an attack like this. Nobody likes updating their electronics because it's inconvenient and sometimes a pain in the ass but taking some of your time to update your shit is going to be worth avoiding a headache of doing damage control in the future in the event of a cyberattack. Updates are annoying but they are there for a reason, it's to have you be better prepared to fare against attacks like this.
The Sharty got their lulz but their victory may be short-lived because I'm pretty sure 4chan is talking to the glowies about this incident. 4chan should learn from this and next time don't neglect their cybersecuirty in the future.
Furthermore, if you are going to commit a crime online, keep your mouth shut because the term "We do a little trolling" is not a legal defense in a criminal court of law.