Folding ideas has a video on vidme that goes into this. A competitor that can't sell itself on features will inevitably gain traction most with those banned from the original platform. Currently that means a new platform will have very angry, very extreme voices. That is a terrible way to start a platform.
A quote that ringed in my mind for years after wondering why this keeps happening.
>The moral of the story is: if you’re against witch-hunts, and you promise to found your own little utopian community where witch-hunts will never happen, your new society will end up consisting of approximately three principled civil libertarians and seven zillion witches. It will be a terrible place to live even if witch-hunts are genuinely wrong.
For the most part, people are fine as long as the boat does rock TOO much, and for the most part Reddit's boat hasn't rocked to the extent Digg did back in the day. It may not even be possible for that to happen with the current population of users. Digg's exodus happened in 2005-6 right before the big boom of social media in 2008-10. The users were generally pretty saavy back then.
These days? Everyone uses social media, and inevitably with any mainstream, most people will only use it very casually, perhaps amongst a small friend group or for very casual browsing. They never comment,they may never even check comments. As long as the content comes, they won't even be aware of the sausage underneat from power users. But they are also the real lifeblood of the site.
These sorts of sites may be too big to fail now. You can't promote a site based on "hey we're not X". It just needs to have the right content at the right time a la TikTok. Sadly, one big incentive of that may include monetizing people for making posts and participating, and that sort of goes against the whole premise of the classic internet forums of the 90's/00's
Here is the video: https://youtu.be/r3snVCRo_bI