Yes, OCaml is older! Yes, OCaml circa 2015 is a useful language! But also, yes, OCaml has gained multiple useful features since 2015! In part because its development is driver by many, many people. And no, BuckleScript doesn't have some of those features as of May 2020! And it's not an indictment of Reason, but it is also a true statement that Reason/BS are lagging behind compared to what OCaml has to offer!