Bemused,
If we assume for the moment that there are more women in the shidduch market than there are men (which is the basis of the age gap issue), would you not agree one logical method of addressing the root of the issue is to reinstate polygamy?
(Note I am not trying to say this is the only reason to reinstate polygamy. But sticking to the age gap discussion for the moment this would seemingly be addressing a root of the problem. And that is the issue I understand haifagirl is attempting to address as well.)