BTW, the banks (not the central banks) hate the M0 layer (banknotes), because it forces them to hold dirty cash in their safes and convert their liabilities (M1) into M0 which can be used outside their payment system. Banks also hate CBDCs because it disintermediates people from their systems, and enables people to be direct deposit holders of with the central bank.
I was never a fan of CBDCs, but CBDCs still could be the lesser evil to the existing payment systems. I have always been aware that opposition to CBDCs could play into something far worse, total surveillance payment systems.
Fortunately, we have the exit option of bitcoin, and I firmly believe we can build a universal payment system using Lightning and ecash. This will make CBDCs, stablecoins, and eventually all fiat currencies moot.