Cashless has its merits but it also certainly has its restrictions as well. I am not entirely worried about the banking system going down; it can certainly get hacked but these banks are now so big that they do whatever they can to ensure their continuity. I am worried however at the implications of using exclusively cash in a data driven world. They would love if they could track every single transaction a person makes. I use mostly credit cards on purchases but there are still some transactions I do with exclusively cash; if I go to a small business and am only spending a couple dollars I won't put it on a card, I will give them cash because I know it helps them more. If I go to a large chain like CVS or anything of the sort I would charge .05 cents if I could because those types of businesses are decimating the small business sector.
On the other hand you certainly have crypto and the financial revolution associated with that. I could do all kinds of transactions anywhere in the world with some crypto exchanging so that's a great benefit.