He also wrote the best book for JavaScript, JavaScript: The Good Parts.
JS is pretty bad, but it's so ubiquitous now that I don't know if anyone can create a replacement with enough traction for one of the big browsers to start supporting it.
Web assembly is catching on, which can theoretically be compiled from any language.
It's not exactly the same, since you're not dealing with the classic Layout+Style+Behavior model of HTML, CSS, and JS, but it's becoming pretty powerful and a few UI frameworks already support it.
I think it'd be possible to create a replacement, assuming you're a large company that ships your own browser (not naming names...). If you have enough market share/"killer apps" then it might be adopted (maybe?).
Now, ditching JS is a whole nother ballgame, and yeah, I don't see that happening any time soon!
One of them tried it, they had a Monopoly and tried to push their Basic (not naming names) but it didn't take off. I can't believe I am saying this but I kinda wish it had worked.