It's a little scary to hear the word "die" for crypto currency,
crypto currency for me has become a job, because my income is on trading and investing,
if cryptocurrencies die, of course this will be a great history and can not be forgotten, hopefully.
Bitcoin and other cryptocurrencies will always be alive.
Everything has to die one day, and when one day we will find some technology better than blockchain, then surely we will migrate to that. World is dynamic and it's better that way! We gotta attach then detach then attach. Once there were currencies we used which were cows, goats, but then we started to trade with gold.
Technology does evolved and progress thats why we can definitely see up lots of changes if we do based up even on simpliest things like appliances or as simple as mobile phones or
way of communication and as you mentioned where theres always a possibility for crypto to be replaced yet nothing do last out forever but if we do just base off on how
revolutionary this tech is then its safe to presume that this will remain for a while or longer years in the future.It all talks about relevance and actual utility.
Things cant just go that too far or be mainly in used if it doesnt really have an actual purpose or cant be use by the masses or making things convenient and accessible.
So things might not be that permanent but we can presume that Crypto will live for more longer years to come but doesnt mean that i cant possibly die.