That's mainly my point. The browser is the game engine, the web app is a game running it, but the way UI interactivity, components, etc, are abstracted in such

That's mainly my point. The browser is the game engine, the web app is a game running it, but the way UI interactivity, components, etc, are abstracted in such a way that the tools end up creating a lot of problems instead of solving them. It's hard to summarize in short form but I think tools would be much better if the underlying abstraction was better. HTML and CSS is a crude way of specifying elements rendering in a viewport, and its main usefulness is really in the past when computers were much less powerful.