Those are all features of React or the React JSX transform, not JSX. Other JSX transforms or frameworks using them may or may not share any or all of them. (JSX is not only used in React.)
Ah. So we're comparing a specific templating language (Svelte) with an idealized and nonexistent version of JSX (JSX is a non-standard extension that has different flavors depending on what underlying framework, and versions of a framework, you use).
