From the OP, i don't think this is what is meant for what you are saying.

Tools like Claude and the like can, and do. This is just a utility to make the process easier.

That's very different from scripting together what is effectively a whitebox test against document ids which is what people do with things like playwright. Replacing manual QA like that could be valuable.

A few days ago I had a interaction with codex that roughly went as follows, "this chat window is scrolling off screen, fix", "I've fixed it", "No you didn't", "You are totally right, I'm fixing it now", "still broken", "please use a headless browser to look at the thing and then fix it", "....", "I see the problem now, I'm implementing a fix and verifying the fix with the browser", etc. This took a few tries and it eventually nailed it. And added the e2e test of course.

I usually prompt codex with screenshots for layout issues as well. One of the nice things of their desktop app relative to the cli is that pasting screenshots works.

A lot of our QA practices are still rooted in us checking stuff manually. We need to get ourselves out of the loop as much as possible. Tools like this make that easier.

I think I recall Mozilla pioneering regression testing of their layout engine using screenshots about a quarter century ago. They had a lot of stuff landing in their browser that could trigger all sorts of weird regressions. If screenshots changed without good reason, that was a bug. Very simple mechanism and very effective. We can do better these days.