That was also my first thought, references, virtual memory, etc. But I insist the value is incorrect. The measurement units got mixed up. You cannot say X Tb (virtual space) of Y Tb (physical space). These are different units! I can see how Apple tried boasting some inflated numbers to impress users, just like they try to sell 8gb mbp saying it is same amount as the old 16gb.

By the principle of least surprise, the reasonable expectation is to show used disk size is less than total size. It is reasonable for both technical and nontechnical users.