People are so enamoured by 4chan precisely because it isn't like reddit. Reddit, Facebook or any social media platform that rewards users with up votes, karma, reputation, likes or whatever creates a system in which people want to please others and develop reputations they have to uphold. 4chan is free from those chains and people are able to freely throw ideas into the mix. This is why 4chan has been so instrumental in coming up thousands of memes that define internet culture today. Reddit, Facebook and others are usually consumers of those memes rather than generators.
I know this is a massive generalization, but that's been my impression being on digg, reddit, Twitter and 4chan for 10 years now.
The problem is that a lot of the original 4chan users either moved on or just grew up and at the same time 4chan got over taken by alt-light type folks. I still think the basic idea of 4chan has a lot to offer that maybe could be replicated on an other platform, with a fresh set of people.
