Server application development is just much different than UI/client development.
It's easy to make JS work on the server like it's easy to make anything viable on the server: it's just one machine running your code, and the runtime only has to interoperate with a well known interface (the OS) that barely changes. And then consider that a web server's interface to the "user" is over a single, abstract port.
In a browser application, you have to interface with JS to drive the UI building blocks (DOM and company). And the web API is async. And you have to build an interactive UI. And abstractions on top of all this are extremely leaky because they are hard to simply paper over and pretend they don't exist like you can on the server.
Often when I see a JS replacement on the browser, it seems to offer very little over JS beyond "hey look, it's not JS" which just isn't enough to justify the penalty.
Finally, the hard part of UI development is stuff like state management and deciding when things should rerender. Switching to a different language alone doesn't give you that. Figuring out a solution in JS, like MobX + React for example, probably does more for you than trying to make a whole new language work.
It's easy to make JS work on the server like it's easy to make anything viable on the server: it's just one machine running your code, and the runtime only has to interoperate with a well known interface (the OS) that barely changes. And then consider that a web server's interface to the "user" is over a single, abstract port.
In a browser application, you have to interface with JS to drive the UI building blocks (DOM and company). And the web API is async. And you have to build an interactive UI. And abstractions on top of all this are extremely leaky because they are hard to simply paper over and pretend they don't exist like you can on the server.
Often when I see a JS replacement on the browser, it seems to offer very little over JS beyond "hey look, it's not JS" which just isn't enough to justify the penalty.
Finally, the hard part of UI development is stuff like state management and deciding when things should rerender. Switching to a different language alone doesn't give you that. Figuring out a solution in JS, like MobX + React for example, probably does more for you than trying to make a whole new language work.