Nobody used to research all the science of how certain mounts affected the sound of a drum back then. It was more a matter of positioning.
And, actually, some kits that have the old mounts, sound great when the resonant frequencies between the mounted tom and bass drum start to match up because they are connected to each other more directly. I have experienced that phenomenon many times with "open" (unmuffled) bop kits. The whole thing starts to vibrate!
Generally, modern drums have more of the long sustaining resonance than a lot vintage drums do comparatively...but the warmer, rounder tones usually are associated with vintage drums...Again, generally-speaking. That has to do with a lot of things, though....not just the mounts.