The upsell opportunity isn't worth anywhere near $50 though. I suspect it acts as a price discrimination filter. You make people jump through hoops (ie. installing an app) to save some money, with the expectation that people who are willing to jump through hoops are more price sensitive, and would also be willing to switch to another airline.
They already charge that and more if you have to check-in at the airport for any reason. And you cannot check-in online without making an account with them. Ryanair is grift squared.
That said I never had problems boarding with a PDF displayed on the phone screen. Unfortunate that they're going away.
