It is if you live a mostly cash-less life. I don’t typically carry any cash on me and don’t pay in cash, which means I often also don’t have any cash at home.

Card payments, contactless payments, Apple Pay, metro/travel cards and banks/financial institutions with fancy mobile apps have meant that I rarely if ever need cash.

No, but it's less convenient, less trackable, and less safe than e.g. a credit card.