And, IMHO, in the long term (a few years) they will steadily lose viewers to sites with a better algorithm for quality (insightful and informative) if they don't make these changes.
I'd say that Reddit has more to worry about from niche copycats than another large site. Why go to Reddit for your celeb gossip and pictures of cats with dumb text when there's a site dedicated to it? It's like oh-mah-gawd-with-justin-timberlake on top awesome, without all the nerdy stuff that makes my brain hurt.