I guess that's true, I didn't think about that. But i think that you'd probably not be using cockroachdb if you were fine with what postgres offers. Cockroach might be compatible, but it really isn't "comparable" in terms of use cases and deployment imo. I might be totally wrong though, I have not been following it and Postgres closely since some time around 2021?
It's useful to use a Postgres-compatible syntax. The point of Cockroach was always to compete with globe-spanning DBs like Spanner, not with (possibly) sharded PG.