Are you asking for the curriculum to teach Svelte and Tailwind, or just that one of the example projects uses it?
Adding Svelte and Tailwind to the curriculum would take a lot of work. Both are still kind of niche compared to React and Bootstrap. I doubt you will see them added to the curriculum anytime soon, if ever (more likely).
fCC can’t teach everything as part of the curriculum as it takes far too much work and there just isn’t enough manpower. But the YouTube channel has tutorials from different content creators, including projects that use Svelte and Tailwind (maybe not together).
Also, the Svelte docs are among the best there is and you can pretty much learn it just by reading the docs. The Tailwind docs are pretty good as well.