Almost all phone apps could be a web app
Also iOS accessibility screen reader APIs are way better than the web. Accessibility actions for instance are great.
Even if you could ship chrome renderer on iOS you won’t be able to make a mobile web app feel as good as an iOS app. The little details, animations, and microinteractions that come with native apps are better, plus there are other less visiual capabilities like background uploads and prefetching. The moment you need something like an in app camera, a native app is going to be so much better.
I am old enough to remember the days of Internet Explorer, I can tell you that it was not fun. It is a blessing that we can at least deliver some pretty decent web apps today, and we should keep pushing for it.