It is not very different from mustache, or other older template engines and it's really needed because there is no conditional html rendering, loops etc in the HTML spec itself, I like that more than how Vue does.

But otherwise, Svelte has a very low surface, everything else is just standard vanilla JS/Html, also one thing that Svelte has over other frameworks is that vanilla JS libraries just work, no need for a wrapper any.

Some devs point at Svelte and say, “not many libraries, it can’t be very good!” What they don’t realize is it doesn’t need a cottage industry of tiny adapter libraries, JS stuff works fine.