IDK, it seems like old reddit did just fine without even trying that hard. The DOM and surrounding JS API is already a high level GUI framework, and the post illustrates that it's perfectly capable of doing useful interactions >60fps. I personally love working with native code, but the modern browser is capable of producing fast interfaces that saturate human senses without it. If you write JS like a C programmer would, it will usually be quite fast, even if it's not optimal. If you write native apps in C++ like a modern JS programmer - frameworks and deps with abandon - it will be a stuttery mess.

When the DOM is not enough, there's already WebGL and WASM. A vanishingly small sliver of use cases can't saturate human senses with these tools, and the slowest, jankiest websites tend to be the least deserving of them (ie: why is jira slow? It's literally a text box with a handful of buttons on the side!).