How does today’s banking system differ from banking 25 years ago?

Very simple: 25 years earlier, there was no concept of phone banking, mobile banking, or online banking. Everything was to be done at the branch. Sure in some countries, the facilities were slowly coming online to check balances, etc. but the bulk/majority of transaction-related services were all offline.

You pretty much had to go to the branch for everything related to authenticating yourself and getting a signature on a transaction.