Blockchain system espeically the bitcoin blockchain system comprises of a supply of 21 million bitcoins out of which more than 4 million are yet to be mined. So value of anything is determined by its future earning potential. If someone becomes the owner of such system he can take away all the remaining unmined bitcoins. Therefore setting up a value of say 100 bitcoins for the whole system is like undermining its importance. I think systwm is worth atleast a million bitcoins.