If you get lucky and get a lenient app reviewer, you might be able to sneak a PWA onto the App Store this way, but even if you do get approved, you're just as likely to get rejected when submitting a bug fix or compatibility update. (This has happened to me a number of times before.)
> 4.2 Minimum Functionality
> Your app should include features, content, and UI that elevate it beyond a repackaged website. If your app is not particularly useful, unique, or “app-like,” it doesn’t belong on the App Store. If your App doesn’t provide some sort of lasting entertainment value or adequate utility, it may not be accepted. Apps that are simply a song or movie should be submitted to the iTunes Store. Apps that are simply a book or game guide should be submitted to the Apple Books Store.
> 4.2.2 Other than catalogs, apps shouldn’t primarily be marketing materials, advertisements, web clippings, content aggregators, or a collection of links.
A "web clipping" is Apple's way of referring to a web site zipped up in a WebView, and that's what rule 4.2.2 explicitly forbids.
Apple has rejected a bunch of PWAs wrapped up in WebViews like this over the years, and when they do, they're normally rejected under 4.2.2. Apple doesn't always notice, but they notice just often enough to make this an unacceptable risk for any app you actually care about.
IMO the big mistake PWA Builder is making here is that (per OP blog post) they do not offer any "iOS-specific integrations."
> Our template doesn’t include support for iOS-specific functionality like Apple Pay, Sign In with Apple, HealthKit, etc.
Those iOS-specific integrations are the only thing that would make these PWAs allowable under rule 4.2. I have gotten PWA games approved by pointing out that they support Game Center, for example.
Overall, I think PWA Builder is off to a good start, but they need a lot more work to be viable.