@mnemonicmonkeys@sh.itjust.works

I'm Brazilian and many Brazilian banks require apps, be it for generating a unique code (e.g. Itaú's iToken) to authorize/authenticate, to scan a QR code every time the Web client requests an action (e.g. Mercado Pago and Santander), or even to do mobile-only transactions such as Pix (Brazilian instant payment/transfer) because our Central Bank (BACEN, who created and maintains Pix nationwide) requires banks to limit Pix in a per-device basis. The latter is crucial because Pix became the main payment method around here, and it can't be done through Web browsers.

Then, there are the "safety measures" inherent to these banking apps, so they refuse to work outside rawdogged Android/iOS. Even enabling "Developer mode" or having some apps installed (such as Termux; apps can see which other apps you have installed) is enough for some banks to refuse logging in (and certain banking apps won't even tell why, just some generic error message).

Also, depending on where a person works, the employer may require the employee to receive their paycheck at a specific bank, which in turn will require an app if the employee is willing to use their own paycheck to pay their bills. Banks have been trying to push their mobile internet banking to their customers, with many banks (such as Bradesco) closing many of their physical branches so people have no nearby ATMs to do banking things.

Finally, even browser-based internet banking (e.g. Caixa Econômica Federal) sometimes require the installation of software akin to kernel-level anti-cheat because "muh security", and some will support neither Linux nor virtualized Windows (most (if not all) virtualization hypervisors can be easily detected by techniques such as the Red-Pill).

So it's not as easy as "use the browser versions", unfortunately.