BTC value to fiat curency can be irrelevant, once the whole chains can operate in it.
You buy TV with BTC
Seller has bought it with BTC, also paid shipping with with BTC
TV manufacturer has bought coponents and labor with BTC
and so on
That's an easy one to answer: it will never happen because it can't happen. If the employees at the retailer and manufacturer get paid in bitcoins, how do they pay income tax? How is sales tax paid on the TV? Governments will never accept bitcoins as payment just like gold, silver, diamonds etc are not usable as tax payments today.
Now it would be possible to get cute and say the employees don't have any income as they get paid in bitcoins instead of dollars, but try explaining that to a judge when the employee is taken to court for tax evasion (the representing lawyer will demand dollars instead of bitcoins too).