For your first question, IMO the purported advantage is mainly convention at scale. There's nothing inherently wrong with raw CSS in style tags or other authoring models (well, except CSS-in-JS at runtime...). Tailwind is one simple authoring model that works at scale without fuss and bikeshedding. Wrote up my experience with the advantages and disadvantages on this though a bit ago to be able to point to[1].
For the second question, depends on your definition of "meaningful" I guess. I doubt the original goal was to make money. There's OSS less prolific than Tailwind that makes money. Is it unreasonable for those projects to seek ways to compensate their projects?
For the second question, depends on your definition of "meaningful" I guess. I doubt the original goal was to make money. There's OSS less prolific than Tailwind that makes money. Is it unreasonable for those projects to seek ways to compensate their projects?
[1] https://wlls.dev/blog/on-tailwind