I don't know the real scoop, but the deeds typically read "to the highest point of land," so I am positive that there is no situation in which a landowner owns the bottom third of the cliff and not also the part above it.

In fact, that bottom third is extremely dirty, loose, and almost always easy (I say this from having climbed up it BITD when certain landowners let us approach from the bottom.) I guess there might be a touch of interesting climbing on it somewhere if someone wanted to do a massive cleaning project, but I can't conceive of anyone wanting to bother, given the vast resources of much better rock available elsewhere in the Gunks.

So as far as I know, the avoidance of the bottom part has been because there came a time when there was no access from the bottom of the cliff any more and no one in their right mind, having appraoched from the top, would be interested in rappelling down that bottom part in order to climb back up it.