The initial implementation of JavaScript was rushed and ended up with strange, seemingly broken behavior in some places.

The WAT talk (https://www.destroyallsoftware.com/talks/wat) by Gary Bernhardt shows some of the JavaScript strangeness.

This used to be more of a thing than it is now, in my experience. Culturally, it took a while for the perception of Javascript to change from "that janky language you had to use to animate web pages" to a general purpose language on the level of Python or Ruby. Node/React/Vue/etc. have been around long enough now that I think most of that has died out, though obviously, many still have a personal distaste for the language.

“There are only two kinds of languages: the ones people complain about and the ones nobody uses.”

-Bjarne Strostrup

Imo it's mostly due to the sheer number of people using it. More users --> more complaints.

With typescript growing more popular fewer have the same complaints -- things are changing