Why has Medium become such a trash fire?

Yeah, Medium has always been recommending clickbait and sensationalist posts, yet after using it for nearly six years, it has become unbearable. Now you often come across plagiarism of poor articles from other sites and straight-up advertising. Some even actively recommended by Medium.

Personally, I hardly ever read posts and stopped checking Medium altogether shortly after learning that I'm no longer eligible to be part of their Partner Program, although I believe some of my posts still are pay-walled (Medium did miss their first deadline to implement the new requirements in January, as far as I know). I made very few bucks, one month nothing and the other more than $2 for old posts I published years ago that barely attracted reads. The algorithm is comically random and I can't say that being a member brought me any benefits, despite the better search result rankings on Google. It wouldn't have opted for a membership if it wouldn't be a de-facto requirement to reach anybody, as non-membership does not attract any readers anymore. It really isn't worth all the hassle and I'm more satisfied with a minimal blog on WriteFreely.

And considering that even the people behind Medium don't seem to know what they really want - they re-brand their site every two years - and cba to keep a minimal UI minimal, I doubt that Medium will ever improve. Poor content just seems to sell better.

Deeply agreed, I observed a ton of clickbait and misleading title on Medium these days. Some writers try too hard to catch our attention with fascinating title, only to keep people reading long wall of text that does not seem to be coherent at all. Most of the time, these look like the output of another similar article put through QuillBot.

I guess it is mostly because of their partnership model with writers, because writers are paid monthly based on how much time Medium members spend reading their stories. The longer members read, the more writers earn.

Because the paywall [alone] is not a suitable filter for the quality.

Medium isn't different from all that recipe sites, it is just the payment [or the hope of it] is semi-direct there instead of an indirect ads payouts. As with recipes you can't publish 3 articles a year and reap hundreds, you need to pump it constantly so you will have a higher chance to catch even a small fry.

Also the site design (at least the default one?) sucks, IMO. Why do the page needs to be 3xFullHD screens for a ~2500 char article (not including ad-footer)? Why do I see an essentially mobile presentation with 20px (why px?!) fonts on a landscape FullHD screen?

The paywall made it seem like a legit platform, the content creators no longer make an effort to write good content, but craft compelling titles and hope for visitors to languish on the page for payout.