Ev Williams is not a fan of the increasingly homogenised media he currently sees, with its emphasis on feeding the great, gaping maw of platforms like Twitter and Facebook too often producing what he describes as tantamount to junk food.

“It’s understandable why media on the web is like it is today,” Williams tells the Guardian. “That’s not to say there’s not a lot of great stuff out there, but a lot of people are dissatisfied with it. A lot of journalists who want to do great stuff are dissatisfied. Advertisers and brands are dissatisfied. We’re still stuck in some very naive thinking, with the idea that people consuming media means that’s what they want – it’s like, well, we put junk food in front of them and they ate that, so that must be what they want.”

That view may strike many as slightly ironic, given Williams was a co-founder and former chief executive of Twitter, which has just celebrated its 10th birthday. But while he is now dedicated to his own project, Medium, which has become a magnet for pretty much anyone looking to put their writing on the web, he says both services are at their root about democratising and simplifying publishing and access to information.

“I’ve been working on publishing systems on the internet for my entire career, which is coming up on 20 years now,” says Williams. “When I stepped back from operations at Twitter, I thought, OK, what’s next? There was no longer this need to make it easy. We’d checked that box. It’s easy to create a website. It’s even easier to send a tweet. But it turns out it wasn’t the case that more information would automatically make us all smarter as individuals or as a society. There was still something missing and broken with the system we’re relying on to get our information, that told us how to understand the world.”

The point, he says, is fixing the feedback loops that drive the production of so much junk. “I think a lot about systems which are dynamic and about how feedback loops drive behaviour,” Williams explains.

“If you look at feedback loops like likes and retweets, they’ve been very carefully crafted to maximise certain types of behaviours. But if we reward people based on a measurement system where there’s literally no difference between a one-second page view or reading something that brought them value or changed their mind, it’s like – your job is feeding people, but all you’re measuring is maximising calorie delivery. So what you’d learn is that junk food is more efficient than healthy, nourishing food.”

As Medium’s chief executive, Williams has built what the late New York Times media columnist David Carr once described as a “typewriter for the web”. It’s actually many things at once – a content management system for writers, for example, as well as a storehouse for musings from professional and non-professional creators.

The company raised another $57m late last year in a round led by venture capital firm Andreessen Horowitz and has hosted the writing of everyone from individual bloggers to Hillary Clinton’s campaign manager Robby Mook, who took to Medium last week to slam the campaign of Bernie Sanders as lacking a “clear path” to the US presidential nomination.

Tech firms turn frequently to Medium to announce new products or company news, and the self-styled “place to read, write and interact with the stories that matter most to you” supplements user-generated content with fare from staff writers like former Newsweek editor Steven Levy, who leads Medium’s technology site, Backchannel. Williams & co have been refining the approach since Medium’s launch, for example by closing some Medium sites last summer and adjusting the direction and budgets of others. It also spun off its publication Matter, which will become a media company called Matter Studios owned by Williams. It will help finance and support media projects from podcasts to books to TV and video, among other things.

Medium has also recently attracted smaller publishers like the Awl, the Hairpin and Monday Note to migrate to it, with content from others such as Time Inc’s Money on the way too.

New features, such as providing a way to launch paid memberships that generate revenue from readers, are meant to accelerate that same shift and entice even more publishers.

All of which is to say that the service is maturing under Williams’ direction – as is Twitter, which he helps guide today from his seat on the board. Yet challenges for Twitter, which has seen its share price hit hard by slowing user growth, are increasingly very different. Under chief executive and fellow co-founder Jack Dorsey, the company has been working on new features to attract users beyond journalists and celebrities, so as to become more mainstream. Most recently, it announced a deal to live stream 10 Thursday Night US football games in the 2016 season, an experience that will be complemented by other attractions like in-game highlights and pre-game broadcasts from players and teams on Twitter-owned Periscope.

Williams won’t be drawn on the specifics of the deal, but it seems a long way from the idea he and the rest of the founders launched Twitter with – “to create this new information layer and discussion and connection layer we didn’t [have] before”.

Medium is in many ways still trying to serve that function. “I know Ev, I know the people around him – they really love the open web, and kind of wanted to create something that was a medium between the platform stuff of Twitter, Facebook and the sort of Wild West mayhem of the open web,” says internet publishing veteran John Battelle, whose NewCo Shift business publication has just announced it is moving to Medium. “They built this beautiful, well-lit place for people to write – and no one understood it at first. Is it a social network? Is it just another blog thing? In time, it became clear to me. I think it’s still an experiment. It’s still small. It’s not a huge platform, but when he said I’m going to put in my lot with the publishers – I want to be on that train.”

The goal, long term, is to fix those feedback loops which Williams says are driving the industry’s junk food addiction. However he acknowledges that for what he wants to do with Medium to work, he needs to “build a network that has critical mass”. Battelle, somewhat more bluntly, notes that it’s not yet big enough for some publishers to pay attention.

Yet that doesn’t mean it is going to engage in the desperate search for scale that has characterised many other platforms and publishers. “Medium doesn’t need to be the thing you check all day, every day. We’re not looking for addiction,” says Williams. “We’re just looking to give people one or two of what they think are the most important things on a daily basis. Things that they care about, things that change how they think about the world.”

Curriculum vitae

Age 44

Education University of Nebraska–Lincoln (did not graduate)

Career 1996 marketer then code writer, O’Reilly Media, co-founds Pyra Labs 1999 creates Blogger 2003 Google buys Pyra 2004 co-founds Odeo 2006 co-founds Obvious Corp, whose projects include Twitter 2008 CEO, Twitter 2012 creates Medium