[thinkloop]

I'm not sure that's a fair assumption, one of the original sells of a shadow dom was that manipulting the dom directly is extremely slow, so doing as much work away from it is faster.

[ttfkam]

Because React's model requires tracking the entire DOM tree for changes and rewriting whole branches where a change is detected.

Svelte bypasses the whole problem for the most part. https://youtu.be/AdNJ3fydeao?t=247