Your rent is not priced in BTC.
It is funny you mention that. I often read stories about people asking their landlords to accept BTC on the forum and it usually seems to work. Apparently most landlords are just thrilled to be receiving some type of payment on time at all, whether it's Bitcoin or Kyle Bass paying them entirely in nickels. Even more interesting was the case of the guy I know who had rental property and was trying to kick the people out who lived in it in order to install a Bitcoin mining farm.
What part of your rent is not a consistent BTC price month-to-month did you not understand?
The rent is priced in dollars. You convert the exchange rate.
But still, there's an intriguing side point. Is there a fellow who can truthfully brag about living in a "Bitcoin-only" economy, in which he makes his way by earning
BTC and spending
BTC - and not touching fiat?
You're right: such a person - if such a person exists - is almost certainly "living the Bitcoin lifestyle" with the perhaps-unknowing aid of Coinbase, et. al. But the new has gotta grow within the old: that's a law of economic life. The first industrial use for steam engines was not trains, it was pumping water out of mines (a centuries-old extractive industry.)