We can't say that bitcoin or cash are better. They have different function in our everyday lives.
According to the law, for my regular work I receive salary in cash.
It's not possible to receive salary in bitcoin because bitcoin is not recognized as official currency by central bank.
From this salary I pay my everyday expenses, bills, mortgage etc.
Bitcoin I earn on Internet and keep in my wallet.
Some of this funds I invest in online business opportunities, sometimes.
Basically, bitcoin is just source of additional income.
So, for everyday life cash is much better but, as additional income, bitcoin is better.
Yes,I agree with you, but in reality cash is very important because basically every transaction we do it using cash or non cash but not using bitcoin.
even if we transact using bitcoin but can not be used directly because it is still very minimal traders who provide payment using bitcoin so before making a transaction with bitcoin we must exchange it first into the currency in each area in order to facilitate to transact.