>Makes me wonder why not just publish their work online free from the pressure from the editorial bureaucracy. Just put some ads, run subscriptions or donations and maybe sponsors. Don't authors get shit pay anyways since publishers take a massive cut and pay pennies for their work?
That's kind of how Korean webtoons and WNs (Web Novels) work. The problem is exposure, trying to be seen in an online market where the barrier for entry is so low means it's even harder for creators to find success and users to find some good shit, meaning it's harder to make a living off if you go independent. Meanwhile being serialized in a big magazine like WSJ gives you all the attention.
Though editorial bureaucracy can be a nightmare, some mangaka definitely need editors to rein them in so the story doesn't go full retard, which tends to happen rather often in webtoons.
For that matter, the most popular WNs get scouted by publishers to get an official LN adaptation (Youjo Senki and Shield Hero started out as WNs, for example), and if those are popular enough it'll get an anime, because adapting an existing popular LN is usually a safe bet in terms of profit. This pipeline is so well known that some WN/LNs structure themselves in a way as what basically amounts to an anime script to make the prospect of an adaptation even more attractive. That said, the reason you don't see this pipeline with putting your manga out for free on the web is that drawing a manga takes significantly more effort than writing a web novel. Instead of wasting all your effort on the Wild West Internet, you might as well shoot for the big leagues of a known magazine.