You could also write a new translation to the Kata. After making it, drop a suggestion in the comments, saying that you have an update for the Javascript (or other language) version. If it looks good, someone with the approval ability can modify the kata with your fixes.

Not only does that do the community a favor, but it also get's you some bonus honor points!

Codewars' content is (mostly) maintained by volunteers; code won't fix itself, someone has to devote time to it. And there is such a report feature : head to the Discourse section and look at the many issues about the lack of coverage

in the early days of Codewars, rules were much more lax regarding tests coverage; this kata is 9 years old. also, users will upvote absolutely anything, and there is a bandwagoning effect when a solution already has a couple of upvotes because it's displayed on top and will mechanically receive more upvotes (it is mostly begginers who vote on solutions).

these are not valid reasons to dislike Codewars though. rules for new kata are much stricter, and the "bad" upvotes are a social problem, not a technical one