the possibly naive pr{e,o}mise of the early web was that it would be a place for people who created content for the joy of creating it to share said content with people who would discover the delights of gatekeeper-free media consumption. "premium" content, that people were trying to make a living from selling, could go behind a paywall or into subscriber-only emails, the way books and magazines worked pre-web. sadly…
Money is a really great way to reward for the content we need. The fact that this money has to be channeled through ads is the problem. Even if a miraculous solution to this problem is found, i wouldn't expect free content to be of high quality.
for other media, such as music, video and animation, one of the problems is that there is a barrier to creating casual content with decent production values. likewise, something like a play or a movie requires a longer-term and more coordinated effort than just someone sitting in their bedroom writing a story. but i believe that if the means of production were more accesssible, people would put in the effort for the sheer joy of creation. (doctorow's "pirate cinema" is a good read in that regard; the protagonist's art form was creating movies stitched together from clips of other movies. a true creative commons would make that a perfectly viable art form.)
note that history has plenty of examples of really good writers and painters dying in poverty. they were moved to keep creating nonetheless; it's a very powerful human drive.
the one bleak aspect to all of this is that the ability to produce art for free is biased towards people who already have another means of support, and one that leaves them both comfortably-well-off and with free time and energy. yet another way in which a basic income would enrich the world.
edit: i also feel that money-as-a-reward has a deeper problem than the fact that it's currently shackled to ads. once you bring in money (and the implicit idea that the better and more popular your work is, the more money you'll make from it), your incentive is to impose access controls on it, because if there's a way to access something either by paying for it or for free, most people will go the free route. that adds an antagonistic note to the relationship between the producer and the consumer, as well as triggering a spiral of overreach with respect to "intellectual property rights".