Anything that wants to be used as money needs at least sub minute, preferably sub second blocks.
Who says that?! You can not even find a single payment system that has fast settlement. Take credit cards for example, it takes at least 6 months for the payment to be settled or become irreversible. Bank transfers, online payment processors, ... are all the same and take extremely long time to be settled that could be from days to months.
Bitcoin settlements when the payment becomes irreversible is ridiculously fast compared to any other monetary system that takes 10 minutes on average.