Fourteen years ago a good deal of those banks crashed the world economy but are still around because governments decided that their immense loses had to be socialized using taxpayer money. Not my definition of economical healthy.
Before the advent of altcoins and before the fees skyrocketed people were using BTC to pay for stuff. A network that can facilitate this has value. What that value is is a matter of debate, just like it's debatable whether Tesla should be worth ten times as much as Volkswagen.
Any crypto that survives in the long term and will facilitate near-instant global payments at minuscule costs without middlemen will have enough value for a lot of people to want to have it.