Since the introduction of ES2015, JavaScript has actually been a really nice language to work with. It's been really well implemented and optimized by browsers

Since the introduction of ES2015, JavaScript has actually been a really nice language to work with. It's been really well implemented and optimized by browsers lately. So I don't really see a good reason to switch languages suddenly. That being said you'll probably be able to compile and run all sorts of languages for the web with WebAssembly in the near future.