To expand on what the posters mentioned: HN is an international community, and the USA is an outlier in having an ample choice of banks. Many countries only have 3–5 usable banks, and all of them require a phone app for 2FA authentication in order to log into their website. Moreover, it happens that banks remove certain functionality from their websites, so it can only be done through the app.

And beyond that, in some countries the strong authentication for logging into government services has been implemented through banks, and so one cannot visit one’s local tax-authority or healthcare portal without a phone that runs the bank app.

Even in countries where you have a wide choice of banks (the UK, for example) more and more banks are pushing people to use mobile apps. We have the problem of the government and other businesses and organisations pushing people to use apps.

One example is my local bus company only selling certain tickets (monthly ones, for example) on the app. If you do not want to use an app you pay per trip which can be a LOT more expensive (several times as much for a daily commute).