Cam Models - is there such a thing as over the hill?

There are times I hear from models that starting into the business in their 30s is to late. Anyone in their 40s don't have a shot a making money against girls in their 20s.

Does age really come into play when men have such a variety in fetishes and desires including MILF which is a huge market even on tube sites - so why can't that transfer over to camming?