Yes and no. That you can build a hierarchy with Element(attrs, children) where attrs may include callbacks is really decades old. Plain JS does it, react and angular do, and also a million template languages.

The question is, how can we not end up in a spaghetti ball? Your scripting style alone brings nothing to the table.

I would look up to something like Elm, which does answer OP's question.

Qooxdoo: https://qooxdoo.org/

It's a no-html, widget only web framework that's been going for at least 10 years.

Java Swing is decades old (1998?) and does everything you list above. Was even embeddable as a browser applet in all major browsers at the time.

Every swing tutorial out there starts with a good old:

  c = new Container()
  w = new Widget()
  c.add(w)
  w.addActionListener(
    …200 bytes of a functor boilerplate…
  )

Also I don’t know java well, but variable/keyed arguments and closures like in python do not exist there, to my knowledge.

Am I missing something, or maybe you meant something else?