The web is full of misleading garbage, but you can get every book ever written inexpensively or free from some combination of Archive.org and Amazon. Many books are trash, but at least we have some means of sorting them.
The web is a big popularity contest, with Google search / Facebook rank being a modified popularity contest. What's popular and entertaining is unlikely to be what's true or useful.
People are very willing to pay for accurate, useful information. Most people do not need accurate or useful information for the majority of their needs in life -- nor do they even want it as we can tell from their revealed preferences.
The web is not even all that popular compared to television. Judging from the websites of many formerly prestigious magazines, many people just use the web as an enhanced edition of TV Guide with some chat features built in.
TV is many orders of magnitude more popular than computer media in the developed world. Many people are happy to pay TV subscriber fees for inaccurate but entertaining shows. The most popular programs are fantasies and sports games rather than documentary programs.
>I fear that since things have been free for 20+ years, people aren't going to ever pay for written content.
Someone tell Jeff Bezos that all those book sales are illusory. But yes, we should expect the web to more and more be the equivalent of a trash heap of brochures and junk publications pointing people towards higher quality options, with the occasional equivalent of a curated public library (like Archive.org).
>I think people, abstractly, might be fine paying for good content.
They really do when it's important to them. But what people say is important to them when other people are looking is not necessarily what is really important to them.