I agree with the bearer instrument value of cash, but I hope for a bitcoin technology that can eventually replace it in all but the rarest cases. I would accept the need to have some electrical power for something like NFC. But not be dependent on either party having a connection to the internet or bitcoin peer to peer network, i.e., no cellular or wifi. Maybe fedimint or cashu tech could be an answer? Tap two offline phones together to exchange value? I still value cash, but tap to pay is so sweet!