My guess is one or multiple of the alts with billions of coins will actually be used as a currency and derive their value out of the currency function, but it may take a couple of years for everyone to get used to the idea that virtual goods are equal to material goods.
Doesnt make sence. First, it does not matter if coin has million or billions of coins, you just move the decimal elsewhere. Second, if you cant use Bitcoin as a currency because of max transactions per second limitation, you cant use any other decentralized cryptocurrency as a currency neither.