I thought this and was put off at first, but have come to the conclusion that you really don't need redux (I've used it thoroughly for years).

We've been converting a large JS react app to Reason, and strongly typed props solves a lot of problems. Passing props down multiple children is no longer a burden, and you'll never have that "prop spreading madness". For anything that reaaally requires some sort of global state, you can use the new react context api.

The only danger of writing in reasonml is spoiling javascript for yourself