No matter how you cut or transfer bitcoin, your answer is still a tautology. And if the only reason you trade things you can live off of for BTC is because you can sell BTC based on faith, that reason is irrational.
Again, what's irrational and what's not is not down to you to decide.
"Future purchasing power" is irrelevant. I care only that I'll own things I can live off of. Whether this is minus a few percent doesn't bother me.
What if I told you that it's irrational to not care about inflation? What if I told you that I do care if it's minus a few percent?
Why then would I pay even a dime for these features and utilities? Moreover, I can have as many coins as I like. Why would I pay $40K for a single coin if I can have the whole package for free?
Because you can't. Setting up your own altcoin means you're outside Bitcoin, where everybody agrees. You still haven't acknowledged that Bitcoin is worth so much, because of
consensus. You can't comprehend that this is what people evaluate and not numbers in a database.