And for years, it was our most requested feature, by far. We had instructions for how to pin the site to your home screen, and would explain to users how the website does everything an app can do. Still, constant requests for an app. Finally we relented and released one, and very quickly around half our mobile traffic moved to the app without us really trying to nudge people at all.
People just really like apps! I think it suits our mental model of different tools for different uses. We've also found that app users are much more engaged than website users, but of course much of that will be selection bias. Still, I can see how having your app on someone's home screen could provide a significant boost to retention, compared to a website they're liable to forget. For us now, that's the main benefit we see. Certainly don't use any additional data, though I won't argue that other companies don't.
While technically competent people might go:
"Oh neat, I don't even need to install an app, if I just put the website icon onto my home screen."
Most users are like: "Oh my god noooo! Not another way to do something! Aaaaa I cannot cope!" and panic.
I am not claiming it is. But it is different from what some people got introduced to. That's enough already to strike fear.
But what do you mean with websites have been neutered? Didn't HTML, CSS, and JS only got more capabilities over time?
They did, but almost all of them are just there so serve developers, to enable them to build even more sophisticated interactive billboards. The web serves marketing and advertising. So do apps, but the web does it better in many ways.
What I meant by websites being neutered, is along the dimension of empowering users. Webapps as tools that provide functionality and play well with others. Composability, interoperability, end-user authonomy. Those are anathema to modern web.
And as I said, apps ain't better. It's really "pick your poison", whether you want to be fighting with your browser sandbox, or with your OS sandbox - and half of the things you need sit on the server-side anyway, out of your reach.