I'm a fan and paid-up member of Medium, the long-form online publishing platform and reader network. I should declare that I'm not unbiased: I worked there in 2016 and know a few of the people who work on it, although the team and product have changed considerably over the last few years.
A couple of years ago they began to reverse one of the most alarming trends on the internet - independent artists losing the ability to sustainably create their work - and allowed writers to get paid for their work. It's been a roaring success, and the site is now one of the top 100 in the world. More recently still, they've brought paying publications like the Bold Italic into the fold. Although this is reminscent of a failed strategy from a few years ago that ended up really hurting publications like The Establishment, in the context of the Partner Program and Medium Memberships it makes more sense.
What Medium isn't is a generic blogging or publishing platform. It's narrowed its focus into being more like a magazine that everyone can contribute to (and I'm told that more changes are coming in the New Year). In doing so, it inevitably loses some of its early users - and it adds features like a paywall that may drive some casual readers away.
Ironically, many of the people who complain about Medium are the same people who care about surveillance capitalism. Yet the site is the biggest, boldest experiment in non-surveillance social media on the internet: a business that makes money by asking for money, and has aligned itself with its community in doing so. No, you don't build a wholly self-owned digital identity like you do on the indieweb; no, it's not a place for billions of people to put their every waking thought for free. But in building a magazine that anyone can contribute to, Medium has opened the door to a more diverse community of writers sharing their lived experiences and getting paid for it as part of a business model that promotes value over blind engagement and doesn't need to profile you all over the web.
To say that writers should make their work available for free is the height of privilege - and indeed, usually those voices are well-paid white men who make six figure salaries at technology companies. Our society is richer for having more points of view expressed, but not everyone has the time available to do free work. The net result of Medium's strategy is more writers making a living from their work, and therefore more diverse writers sharing their lived experiences. I'm all for that.
Publishing on Medium does not preclude writing on a personal website that you control. You can do both. But just as there's nothing wrong with publishing a long-form piece in a newspaper or a traditional magazine, there's nothing wrong with publishing it on Medium.