But that separation is sometimes the point. A designer tweaking the looks has no chance to break the computation logic, and an engineer tweaking the computation part won't disrupt the design by mistake.

Terseness is good for code golf [1]. I disliked CoffeeScript after writing it for some time: nearly any typo can result in another syntactically correct program which, of course, does not what you wanted the original program to do, or fails the compilation in an unrelated place. A practical language has safety margins, aka some redundancy.

[1]: https://en.wikipedia.org/wiki/Code_golf#Dedicated_golfing_la...

But they're both framework-agnostic.

This snippet works with any framework and any build step.

  <script src="https://unpkg.com/alpinejs@3.x.x/dist/cdn.min.js" defer></script>
  <div x-data="{ 
    today: new Date().toDateString(),
    randomNum: Math.floor(Math.random() \* 100)
  }">
    <p>Today is <span x-text="today"></span></p>
    <p>Random number: <span x-text="randomNum"></span></p>
  </div>

I'll concede that Alpine.js is harder to understand and more verbose than Marko's syntax, but in order to use Marko you have to commit to the Marko framework. If you're willing to choose a framework solely for its JS-in-HTML capabilities, there are much better choices (like SvelteKit that handles JS-in-HTML wonderfully).