You're right in a way. Portal could be thought of as two parts, the raw physics and the raw graphics. But when a lay person makes claims of recreating Portal's secret sauce, they're really implying the portal mechanism which is one part physical and one part graphical.

Literally recreating only the physics portion of Portal would be silly.

And yes I was intentionally trying to be sensationalist back because it's a waste of time being victim to submitter's sensationalist headlines, especially on a technical site such as as this (one would hope).