I think the problem is that this kind of web relies on altruism to work. People have to donate their time, effort, knowledge, and sometimes even personal money (hosting isn't free) to create and maintain these kinds of sites. Meanwhile, there are far more people who would rather attempt to make money doing the same thing, so non-altruistic content ends up outweighing the old-web kind. This has become especially true on YouTube where good content is much harder to make, so the vast majority of creators are pursing some kind of monetary compensation, whether from ads, sponsorship, patrons, merchandise, or something else.