Didn't Josh permanently fuck up 8chan also?
Not really. He did mess up, but they were able to recover, the site was ended by the live-streamed shootings. To give you the lore:
Back in the day 8chan was set up by a crippled man called Frederick Brennan, also known as Hotwheels. It allowed a lot of content too extreme for 4chan, for example
#GamerGate related content. Josh was taken on staff and commissioned with $12,000 to upgrade the site. This led to 8chan developing the usual problems that follow Josh including humongous amounts of child pornography.
Josh was trying to upgrade the software 8chan used to be an enterprise, clustered / web-farmed scalable solution. But this is Josh - he has some basic, 'adequate' knowledge of PHP. His ambitions exceeded his technical abilities and the project failed. In fact Hotwheels wrote a massive hit-piece on Josh on Medium which has been taken down, but which was archived:
Infinity Never: The sad case of the imageboard software that could but never will.
"Three days ago, January 23rd 2016, Joshua and I ate pizza and watched King of the Hill. He was talking about how he had gained weight and it was hard to find clothes for people his size here"
"Things were mostly quiet during this time. A friend of mine told me about modafinil, and since Josh mentions Adderall almost every other time I see him, I decided it would be a great way for him to experiment with something safe."
8chan users were especially upset that the all the IP addresses for users of the beta of Infinity Next were leaked, including the addresses of viewers and posters on the many child pornography boards. They were naturally antsy about the FBI being able to just browse their addresses without a warrant.
All of that being said, when 8chan had a new owner, Jim Watkins, he cleaned it up and removed the child pornography. Josh lived in fear of being murdered and fed to Jim's pigs on his pig farm. For a time 8chan thrived as the shadow of the evil pedophile lord was banished by Jim. What did for 8chan was being used for repeated live-streamings of mass shootings conducted by its users leading to Jim being brought before the US House of Representatives, the US Homeland Security Committee:
Online providers knock 8chan offline after mass shooting.
Jim was not to be counted out, however, and cleverly cooperated with the committee to the extent they praised him after he pointed out 8chan took the livestream down much faster than Facebook and basically made Mark Zuckerberg and big tech look like douches. He relaunched, branding as 8kun. It's basically the same but without /pol/ by that name, although /pnd/ is a close substitute.