I think they've lost the will to do anything creative with Reddit, due to the massive growth of users they've had in the past 5 or 6 years. Reddit is nothing like it used to be 8 or 9 years ago when I joined up. It's become heavily over saturated on pretty much all of the main subreddits at this point.
Something else which really kills good content on that site is the fact that it's so easy to manipulate votes. You don't even have to use paid services to do it, you could just have a group of people all upvote the same post in the first few minutes, or even just do it yourself by changing your IP address and making new accounts. I've seen so much garbage and corporate shill stuff get to the front pages it's ridiculous.
And, the way that some of the subs censor or ban people is outright ridiculous. I know Acid has mentioned bad experience with the mods of bitcoin, IIRC. And, I myself had had some issues with bigger subs banning me because I shared an opinion that was not liked. It's really frustrating, and it's one reason why I only go on reddit maybe once a week anymore, and that's only to check movie news and my own subreddits.