A fair question, and I don't know that I've got the answer, though several answer-shaped possibilities suggest themselves.
One line of thinking has a Neilsen or Arbitron-like rating system that pays based on readership. I think that is ultimately a false lead as it simply rewards popularity.
Another is to employ a basic income approach. Given the number of writers I know who write largely because they can't not, this might work, though it might not be fully sufficient. The prospect of a UBI and some achievements-based revenue might make this more viable: electronic distruibution is gratis, but live performances and physical media might generate additional revenue, as might various services or other arrangements, all on top of a UBI base.
A third way might be to treat creation something like research: it's an activity, and it's funded as a certain overall percent of national income. Divide that by what's seen as a livable wage, and designate that there are so many positions open, and so many to be filled in a given year, that will be paid. Sorting out how to filter out those who really aren't suited to it is the next challenge, though there are various models: guilds, professional recognition (see the Emmy's, Grammy's, Oscars, Pulizter, Peabody, Nobel, Royal Society, AAS, and similar recognitions).
One thing I don't think should happen is for there to be some sort of quarterly or annual "rank and yank", or the general fight over scientific grants funding we now have. There's an article I'd recently seen about productivity of scientists over their careers, and the distribution is ... almost perfectly random. That is, a given scientist might produce some great work early, late, or in the middle of their career, once only or possibly several times. But there's not much rhyme or reason to it.
Creative work generally is something that evolves over time, and takes time. Days, weeks, or months even for a good piece of journalism. Years for a story, play, or film. A lifetime for works of science or philosophy. Take Wittgenstein, who wrote one book and then spent the rest of his life writing another refuting the first.
(And yes, there are prolific examples as well, though often they are best known only for a handful of works. Attention is a zero-sum game. Alexandre Dumas. Isaac Asimov. There's a large literature on Gresham's Law effects in literature, painting, music, drama, and television as well.)
The inputs to writing are information, sources, and investigations. Otherwise, generally, a quite space and not having to worry too much about room, board, heat, water, and light. Excessive remuneration doesn't much seem to help in its production, and a certain frisson may actually help, but only to a point.