For the time being, I believe cash to be superior to Bitcoin. But if they manage to get rid of the money, cryptocurrencyespecially privacy coinswill take its place as the new money.
That's the bet. Cryptocurrencies aren't going to be globally adopted until fiat currency is felt seriously and unreasonably debased. One scenario is that cash is repelled, and central banks introduce CBDC (which isn't as debased as cash, to attract). In fact, the central bank of EU has said this will happen in 2025, if I'm not mistaken.
Cash isn't superior to bitcoin, IMO. It usually annoys me to do the math for change when I'm out with friends. It's also easier to lose, and you don't have the history of your transactions (which is sometimes necessary).