This is a great way of thinking about diversity. As a physics phd student myself I have observed this a lot -- that the students who put together a fantastic dissertation project are often not the ones who come in with a great transcript or who sound the smartest when asking questions in class. I see that other commenters are intent on misunderstanding this, which is a shame.

Edited to add: separate from the discussion about what this means for admitting students or hiring professors, another important part of this is on the education and mentorship side. A uniform academic (or workplace) culture that rewards people who fulfill a narrow conception of merit will exclude people who have a lot to contribute, but are made to feel uncomfortable in that culture and devalued in that conception of merit.