It's the thing that attracts a lot of new beginners who may or may not be interested in the more serious theory that makes programming what it is.
The core data types actually strike a really excellent balance between representing the major distinct paradigms (named collections, unnamed collections, strings, numbers, booleans) while giving you maximum flexibility within them. Its standard library - array functions in particular - has become very mature. FP and OOP concepts are both quite well-supported, and doing async stuff (client or server or otherwise) with promises just smashes every other language I've used in terms of ergonomics.
Much of the above could be said about Python too, but regardless.
TypeScript and Python (with typehints) are the current favorites. Golang seems to be getting up there for me too, but I don't have enough experience with it to actually be able to say that.
There's half a dozen different syntaxes for importing/exporting functions, creating functions, creating objects, etc., and it's all fair game. Then there's the asynchronous nature, so sometimes it's async/await, and sometimes it's promises, and sometimes it's callbacks, sometimes all happening in the same function.
And then on top of that there's all the front-end web frameworks which are like, totally un-opinionated, man, except for the parts where they're implicitly super opinionated.
I imagine that accounts for a lot of bad Javascript and PHP code. By the time I wrote any C++ or Python professionally I had a CS degree and a decade of programing experience.
I'm not saying that a language should only offer one approach to a problem, but there should be general guardrails and guidelines. A shared vocabulary. None of that exists in modern JS
- Bjarne Stroustrup
The fact that we have things like the Wayback Machine is a testament to how this approach, while terrible for developers starting out or working in a legacy codebase, has enabled us to preserve what is now a significant portion of contemporary cultural history. AFAIK there is no similar archive of programs for, say, Java or C.
[1] https://standardjs.com/ [2] https://github.com/airbnb/javascript [3] https://prettier.io/ [4] https://eslint.org/
Semicolons could be considered idiomatic or stylistic, for example. Requiring strict equality operators feels more of an idiomatic way to avoid bugs, rather than simply whitespace. Eslint certainly has a number of rules that are more idiomatic than stylistic.
If you're touching on the lack of consistency in, say, open source javascript, I agree, code is all over the place. Also, I think you're looking at a language that has had dramatically more evolution (especially in recent time) than most other popularly used languages. Old code without promises and suffering from callback hell feels archaic.
However, I think if you look at, say, TypeScript repos (which is cheating, I know, it's not javascript), there is more homogeneity, at least from what I've seen.
Of course it evolved. It’s easy to evolve if it was literally nothing in the first place.