It's not that JavaScript is a bad language, it's just easy to write bad code in JavaScript. I don't get it why most people coming from languages you mentioned like to bash JS so much, I used most of these languages in the past or use them currently (mainly Java and Python) and I like JavaScript the most. The problem is most people just don't want to learn JS, they write shitty code because it's easier and than complain how bad the language is. Sure, there are many issues with the language itself, usually because of how flexible it is, but for almost every issue there is a 'good way' of dealing with it.
Unless you are lucky enough to work on only your own code, that it's so easy to write bad code is a massive problem.
My big beef with js is that there's no 'right' way to lay out your code. Trying to figure out how a js module works is always a unnecessarily massive pita.
