Now with the internet, anyone can publish. Unfortunately it has become infeasible to fact check every single person. Even fact checking one individual often doesn't pay off, you spend a ton of time checking them, only to get a very small stream of information.
This is the primary problem with self-publishing. Because of this I've pretty much given up on reading most self-published material. Unless the author comes from a well regarded institution or otherwise there is an easier way for me to judge accuracy I'm just not interested.
No doubt this viewpoint will offend most people here, but to me this is the biggest problem society now faces. Probably even more dangerous than pure opinion, is content that is mostly factually correct, but contains a small lie. This sort of biased content or intentional misinformation is both very hard to identify, and the very effective at propagating lies.
These days I mostly use academic journals, as peer review is at least some form of quality checking. I do also use a few select large news sources, though with less trust. I've given up on medium articles and similar.