Vue and React do bring along the whole runtime and allow introspection, but have abstracted away the browser to a great degree.

The problems really break down like this:

Clojurescript: Doesn't run natively in the browser, requires too much tooling, interactive development during development but doesn't make it into production.

React/Vue: layer of abstraction over native browser APIs, also unacceptably large

Svelte: Not available at runtime

Flippantly, the audience is me, but I'm trying to better put into words why I want this. The idea is to get closer to the experience of developing CL with SLIME/Emacs, where you really are poking around on an active living system. I find that form of development to be the most productive, and it seems like the browser + inspector console is a great potential place for such development with the right set of libs. I want a library that is fully available at run time yet small enough that you can send it into production. And I want to to fully embrace web standards for good or ill rather than try and fix the web via layers of abstraction. Last, I want it to have a very minimal surface area so the whole thing fits in your head, think something like Backbone.js where you could read the whole things annotated code in a day and wrap your head around it.

I appreciate your replies, you've helped me at least try and better refine what I'm thinking of.