The lack of signals isn’t remotely the largest issue with JS, and adding them has minimal impact for most users of JavaScript. The biggest issue is the lack of a standard library, resulting in npm hell in most projects.
> JavaScript has had a fairly minimal standard library, but a trend in TC39 has been to make JS more of a "batteries-included" language, with a high-quality, built-in set of functionality available
I think the description "minimal" is fairer than "no" wrt the standard library.
JS projects exist in npm hell because people have been taught to use a library to save typing 10 characters. No standard library is going to fix. Because someone can just call in a new lib that just curries something in the standard lib with minor improvements like caching.
That's a complaint I've heard since ES3 if not earlier and the trend ever since ES2015 has been to address that so I'm genuinely wondering what you think the JS "standard library" (aka built-ins) is lacking right now.
Given the different environments JS runs in these days, I'm also okay with extending the definition of "standard library" to "things browsers should have as built-ins" or "things Node.js should offer as a built-in module".