I have contended that the only use for cryptocurrency which provides value for people is for anonymous transactions for which cash is not an option or a poor option. The only cryptocurrency that can do this that I know of is Monero. Therefore Monero will have lasting value. Whether you can make money speculating on it is dubious, which is probably why not many people do.
* Note: I am speaking regarding the markets I know; I cannot say anything regarding economies suffering rapid inflation or which lack access to banking
* Note: I am speaking regarding the markets I know; I cannot say anything regarding economies suffering rapid inflation or which lack access to banking