I doubt it.
First of all, I don't think the supply of bitcoins and their ilk is sufficient to provide adequate liquidity in a $20 trillion GDP economy, let alone making purchases of trillions of dollars of imports. Or is the thought that the supply of bitcoins etc in circulation would be increased by having everybody and his brother be able to come up with their own additional competing CC?
In the second place, the Fed currently has the power to exercise some control of the economy by manipulating the money supply and interest rates, and I don't see them giving up that power without a fight.
I guess time will tell though. I don't plan to lose sleep over it.
All of those and many more I can't imagine right now will be part of the CC/digital economy. You correct that the rest of the economy can function as it does now with physical and digital fiat. But the purely digitial portion of the economy will inevitably grow and eventually outpace the fiat physical economy. What do you actually need? Food, shelter, etc What else? The rest can be digital. However you are correct your plumber won't accept bitcoin for the foreseeable future and it's not worth losing sleep over it.
But a few decades from now that will be different and incidentally bitcoin will be dead by then because the PKI won't withstand brute forcing. The new CC's that replace it will be much more interesting.