"value for the economy as a whole"
You've shifted the goalposts there from "has value" to "value for the economy as a whole".
If I have money in a ponzi and can exit at that point in time, my stake has value. Later it might not, but at that point it does.
So you are saying that drcode means cryptocurrency has value as a ponzi scheme?
?!? No.
Just because some people can get out more than they put in doesn't mean a ponzi scheme has created any value for the economy as a whole.