But there's no direct trading going on at that state to ensure they deliver what is claimed, the research "product" is just dumped into papers. And those papers serve as an impediment to subsequent researchers, since you can't publish or get funded for the same thing that's already been done and supposedly proven by someone else. Of course you wouldn't have to if they had really solved the problem. But they just threw together some minimal effort to stick their name on it first before moving on to the next low-hanging fruit somewhere else. Doing a literature review can be really frustrating.
There is a small and somewhat obscure but relatively stable middle - low-budget, high-quality videos. I attribute its survival to two things: some live off Patreon donations and occasional sponsorship deals, others live because the creators have an actual dayjob, and they do YouTube as a hobby. This is similar to blogs - best ones are done on the side, with no expectation of revenue.
One answer to all these propositions is that the valuable stuff is still there, you just have an additional flood of mediocre boring predictable stuff.
I don't think this is true for most things with a mass market. I think products which have efficiencies of scale - or low marginal costs of reproduction - suck up more capital, which raises certain basic levels of standards and polish and marketing, but also greatly increases capital risk and thus reduces investor risk appetite for product novelty. These mass market products starve the mid-market of attention, which makes the mid-market less capital efficient, which means the mid-market needs to get cheaper and cheaper, lose polish, until it's less attractive to the mass market of consumers, and so on in a spiral until a certain spartan rawness becomes its own aesthetic - indie games, indie films, indie music.
I think there's a concrete example which demonstrates the actual absence of that long tail of interesting content, and not just that it's harder to find: blogs.
Blogs were great in the mid 2000s. The market did two things: it matured - the best blogs got more mindshare and turned into something closer to media organizations, much more capital intensive with full time paid writers, while and Facebook and Twitter sucked up the mass market of newsfeed consumers, both on the producer and consumer side, making it easier to produce low-value inanities and easier to consume tidbits from celebrities. This sucked the air of attention from blogs; being long-form, they were too hard to write and too long to read; and being unpaid, they didn't have slick editors or snazzy design. So a lot of them shrivelled up. There are still niche blogs, plenty of them, but a lot fewer - and we can track this loss, because we have (or had) them in our newsreaders.