Digg was big during the second Bush Administration. I was a daily browser of the site, and I recall it being obvious that right-wing conservatives were brigading. They even called themselves the bury brigade. Bury was the Digg equivalent of Reddit's downvote. Reddit seems to have been taken down in a similar way, except it looks like this time its left-wing liberals.

The owner of Digg was a greedy bastard. He kept holding out for more money. He saw Digg as being worth billions and billions of dollars. He kept turning down offers to sell because they weren't high enough.

Meanwhile, he kept making changes to the code. He kept "fixing" Digg. Each change that he made angered the users a little bit more. Eventually, he realized that he was broke. So, he started pushing advertising. He signed a deal with Microsoft/Yahoo and was pushing god-awful ads that were annoying as fuck. Eventually, he lost all pretense of "community driven" and "user oriented" -- he just started selling out left and right. Paid placement? Sure! Promoted content? Sure! Rigged voting? Sure! Anything to make a buck.

The users got fed up with it and went to Reddit which, at the time, was open and fair. They were young and hungry and desperate for users. Reddit had a good run of about 8 years. But, they started to get taken over by corporate interests. Reddit is owned by Condé Nast. When the site first started, the parent company didn't care because there was no traffic. But, as the site grew the parent company became more interested in what was going on. Then, they started to have a direct hand in the manipulation of Reddit. Soon, it was fully compromised and sold out to the highest bidder. It became more about the advertisers and the money than the users.

It's a warning to all Internet communities. If you lose track of your original mission and you start to cater to advertisers more than your users you will fail. Also: "if it ain't broke, don't fix it." Users hate when you change things for no good reason.

I don't think it was 'orchestrated' by some nefarious group (but, the intelligence agencies did have an interest in using both sites). I think it was greed that did both sites in. They wanted to make a platform that is friendly to advertisers and business so they could make money. But, that's not what the end-users wanted.

The top comment in this Reddit post is pretty spot on.