Some coins like this may interesting for people who want to out of radar, remove any trace of their transaction which refers to black market or illegal activities from FBI point of view, so those coins cannot develop/adopted so far such as bitcoin, itu will stuck somewhere and drop back if authority begin to trace or ban it.
But that is perfect. In the mean time, they served their purpose, which is the only thing that counts, no ?
There is no other use for crypto in any case.
Coins don't have to last for ever, or climb to the moon. They have to do the thing they were designed for, during their life time. Like any other product.