I prefer that either be allowed.

Greatswords move much faster at impact than do pole arms, hence they deliver much more of a “shocking” strike, which is what causes breakage in the target. Pole arms deliver more of a fast push. That push becomes dangerous not in that it is likely to break whatever it hits, but rather when it delivers a strong enough push, with sufficient mass, it can cause something akin to whiplash. To my mind, this will most likely occur with a padded pole arm, which will probably have more mass. This is not to say that a pole weapon cannot cause a broken bone, but rather that it is much less likely to do so than is a greatsword.

On the other hand, I am very much against weapons that do not act like real weapons. In this category I place pole arms whose striking surface is differentiated from the rest of the weapon by having a layer of duct tape on it. When I pick up a pole arm, I expect it to feel as if it had a steel blade on one end, and to handle accordingly. Also, when the shaft of a pole weapon is being used to block sword blows, I expect the weapon to weigh as much as if it had a sturdy hardwood shaft, and also to handle accordingly.