If I invent a new human language “better than English” and asked everyone in the entire world to stop speaking English and start speaking that new language, no one would listen to me. Because why would they? No matter how compelling that new language is and no matter how much it's claimed to be better than English, that doesn't change the fact that this won't work. There are a lot of books written in English. Lots of businesses around the globe are handled in English. Lots of contracts and documents. Lots of movies, show, novels, and literature. Why would someone abandon English and go learn a new language that no one else speaks yet?

The same with JavaScript. All web developers and also most desktop developers and even embedded systems and everyone that had anything to do with Software, probably know JavaScript for a reason or another. A lot of libraries and frameworks and websites are using it. Now why would they ever switch to anything else? No matter how compelling that new language is.

Even if hypothetically there's a replacement, it'll take a huge amount of time until all web browsers support it. And that would only be for a few websites that still use it. And then a huge amount of time until other people start switching to that new language. And there'll still be support for JavaScript and it'll still be in need.

Some people think that when they say that some technologies are obsolete and dead will make them look futuristic and visionaries. But it makes them look juvenile and unexperienced. Don't listen to them. If a technology exists today, it's there to stay.