There's a thin filter on top of the sensor of every digital camera that can affect lenses designed for film, but I personally only know of 1-2 lenses where it makes a marked difference.

In terms of underperforming, it's hard to define underperforming. Regardless of what some guy on a blog thinks, I have had many clients comment about how impressed they were with portraits I took of them with lenses from 1971 and 1993, and 0 complain about how the same lenses' corners look soft when shooting a test chart wide-open then blowing it up to 400%.