One thing I haven't seen addressed in the post or comments (sorry if it's there and I just missed it) is for apps and websites that sell non-digital goods to customers.
For returning customers, a customer with an app installed is simply going to have a lot less friction to open the installed app and place an order than a customer who has to open their browser, log in again, and then place the order.
That alone is worth the investment for many companies in making an app, even if a minority of customers actually choose to install the app and keep it installed.
If the website is a PWA, it can be installed to the home screen and look and behave just like a native app. You just tap the icon on the home screen. It will remember your login.
And the upside is that you only have to develop one website (instead of a website and 2 separate native apps for iOS and Android).
For returning customers, a customer with an app installed is simply going to have a lot less friction to open the installed app and place an order than a customer who has to open their browser, log in again, and then place the order.
That alone is worth the investment for many companies in making an app, even if a minority of customers actually choose to install the app and keep it installed.