Why is a `transform-react-jsx` required

I was wondering why this example requires the `BabelPlugin`, since TypeScript can transpile `JSX` by itself.

Removing the plugin and using a custom `tsconfig.json` that sets `"jsx"` property to `"react"` works (at least it compiles), but the output seems to be broken. Opening the app in the browser is not possible -> `http://localhost:4444/default/index.jsx `

Is it not possible for FuseBox to compile JSX without any plugins?