If an Alien saw the dollar!
As long as people are willing to trade bitcoin and crypto there will always be value in them. Things only have value if people give them value, for e.g a dollar note.
If an alien came to this planet and saw a pile of dollar notes, they would see it has no real value as it's just pieces of paper no different to toilet roll, and technically has the same practical use as toilet roll.
My point is people give the dollar value in their minds, just like people