Bitcoin is too fragile to be used for 'global economic unity' or anything like that. Try to think in a timespan of beyond 20 years in which it will definitely be hacked/cracked by then or they will find some way to keep the network from functioning in some way or the other. In a best case scenario, we briefly touch something like $20,000 in a speculative bubble before crashing. That is the play here.
No, you have it the wrong way round. Humans are too fragile to be here in 20 years to use Bitcoin. We will be hacked/cracked or some other way to disrupt our network will be found.