Because of the long confirmation time and transaction fee of BTC I doubt if it will gain that adoption of using it as payment, BTC itself is rather a store of value and other alts that complement BTC can be used for payment.
Indeed, in past few weeks many bitcoin user complaining about long confirmation transaction. Its take more than 7 hours my transaction complete. I am believe bitcoin will be store of value and long term investment rather than currency. I am more comfort using bitcoin if bitcoin regulated by government
The delayed transactions of using bitcoin Is one of the major problem and I believed the development team of bitcoin already worked for It to fix as much as possible. To make those costumer well satisfied to use bitcoin for online transaction in blockchain.
Until this is fixed properly, people won't be interested in using bitcoin for daily transactions or other needs. They'll only see it as a hedge against inflation and useless currencies, not as a currency. Unless, of course, fiat crashes and becomes useless overnight.
This can't happen because there's too much vested interest in fiat so it will continue to hold value. Bitcoin is a direct competitor with the most valuable system of exchange. Governments will be issuing e-currencies much further in advance to bitcoin being widely used as a payment system.