Its mine and should be taken with a (large) grain of salt. It is a bold assumption that total network storage will hit 1 Exabyte by year end. I think the potential is there, but a lot hinges on development of the protocol itself which is by far a done job.

The estimate further takes into account payment for storage alone, and not speculative elements that may drive the coin price much higher of course.

But lets just all guess for fun and don't take my estimate as any advice to invest etc etc :-)