I don’t care much about Reason (as I’m not going to use it anyway) - their arguments against currying is more like justifying Baby Duck Syndrome of JS programmers.
Some of their arguments is just not true - especially one about performance - you either create a closure using currying, or you create the same closure using explicit function definition. There is no performance gains in the second case, you just lose readability for no reason.
But I’m surprised that even experienced OCaml developers (@lpw25, for example) believes that currying should be avoided. Having non-curried data constructors is one of my biggest pain points when using OCaml, i.e. it forces you to write
fold (fun x a -> x :: a)
map (fun x -> Some x) l
instead of just
fold (::)
map Some l