To be honest, I don’t think you’ll need to use the app. I get my passes via email and add them to Apple Wallet.
In some airports, printing the pass is actually free, they have a dedicated vending machine just for this.
They are not saying that you can not print the pass yourself, I suspect this move will save a lot of time and money which, ultimately, is a good thing for everyone.
They want to charge a check-in fee if you don’t do it online, I would not be surprised if they have a lot of people wasting time doing it in-person instead of doing it online. This could speed customer who actually have luggage.
What am I missing?