I voted crypto will not die.
It is the future and nothing will kill it easily.
People talked about the 51% attack but it is almost impossible, plus. If one coin dies, some others will raise up and make awesome crypto projects. That wont be a problem for us.
It's not impossible because the bitcoin gold has been getting it. But 51% attack can't be implemented in the POS coin. Bitcoin will never die consider there was a lot of people are using it to store their value.
It will not die and it will always exist straight with the development of the future technology to make our life will be easy.