My guess: the anti-SJW crowd will leave to go to voat (and if we're unlucky, here) and the SJW & neutral crowds will remain, warping reddit into something more along the lines of tumblr with more cat pictures.
On the other hand, even before this recent Pao stuff, reddit had been getting a pretty solid reputation for being an advertising/PR platform. The shilling and advertising is pretty horrendous, and almost all of the default subs are completely overrun by paid content-- if you don't believe me, just take a gander at how frequently McDonalds, Doritos, TacoBell, etc make the front page with content-free posts that are often as simple as a picture of their products.
I guess you can say "avoid the larger subreddits" but there is a lot of content-based shilling too-- try posting anything about Israel or Russia in the context of a serious discussion and see what happens. It isn't a coincidence.
Starting something like this isn't necessarily the death knell, but the inevitable unequal application of it will be.
The incredibly strict anti-trolling policies around HN do make it a great place to come back to years later. Though HN also takes care to engineer the social interactions here too. (scores are hidden, upvotes only until you get to a certain karma level)
I do tend to worry a little about bias and inconsistent enforcement of their policies, but also believe that we'd have to see that play out over time.
Without question the stated goal of "diversity" is noble, valuable and, deserves to be pursued. The problems arise in their definition of diversity. Does it mean what I think it means?
What about their definition of "safe"? We're really going to have to wait and see.
I think calling this the demise of reddit is a bit premature.
Though I also struggle to believe that deleting the extremes will make it a more interesting or compelling place to be around.
There's a reason that maniacs stop taking lithium.
I don't upvote people either.
I believe it is better to elevate good posts/posts that I like, than silencing bad posts/posts that I dislike.
I think there should only be UPvotes.