And this is why React apps end up with bad performance by default. Doesn't crop up in simple tests and light usage, but the bad scaling will catch up with you when you deploy to production.
But you'd be surprised about the "react for the front end of the CLI" part. I used this thing a whole six years ago in a complex interactive CLI and it came off great to use, maintainable and ergonomic. React is just one framework that proscribes to the "UI as declaritive/composable trees" pattern. And that UI doesn't have to be web based. That pattern works for all UI's I've come across.
Its the pattern that is a good reason to do this. And not react/js landscape. That part is probably a bonus for many though.
This project and others like React Native show that it works outside of the DOM: you just render something else instead.
Thinking that React is only helpful for DOM UI seems like a misunderstanding of what React is and what makes it great.
Arguably it makes even more sense than with React. One of the problems with React is that the underlying DOM is a stateful, imperative system, whereas React wants to behaves much more like an immediate-mode system, where the whole UI can be dropped and re-rendered at any time. But the terminal is not stateful like the DOM, and a more immediate-mode paradigm arguably works better in this context than in the browser.