Hm, that's an interesting question. The value I find in the immutability aspect comes from, I think, everything else that comes with it. In being immutable, an

Hm, that's an interesting question. The value I find in the immutability aspect comes from, I think, everything else that comes with it. In being immutable, an action taken has to be explicit, and therefore is trackable and replayable. So while you don't necessarily get much in the way of safety against concurrency (though, let's be honest: there is still asynchronicity in JS even without concurrency), you get a lot of free in terms of state tracking, state replication and state reproduction. This doesn't even mention the benefits around testing and reasoning about pure functions that are reducers.