A democracy is only as effective as its people are educated.
When people are not well educated, they have more trouble than they should discerning real from fake, objectivity from bias, quality from trash. (Obviously there is some subjectivity here, but there is also some ground truth, and I'm talking about the latter.)
The result is that they're more likely to click, read, believe, and share pieces that are sensationalist and low in quality. Consequently, the media companies that write that kind of stuff get all the views and most of the revenue, which they use reinvest to grow and write more of what they're writing. This also incentivizes other media companies to go the same route, and the ones that don't remain largely irrelevant. It also normalizes sensationalist low-quality writing.
To wit: SimilarWeb says the Daily Mail gets 230 million views/month. ProPublica gets 3 million and Democracy Now gets 1.5 million.
I have no idea how a society gets itself out of this downward spiral, besides better educating its people. Or restricting its people's ability to decide what rises to the top (which ofc has its own obvious downsides).