A nice feature of feudalism is that if there’s a shortage of food/peasant ratio the nobility had two factors, instead of just one, that they could adjust.
Your comment is truer and not as dark as you may realize. One of the reasons for the great political stability of Medieval Europe despite the lack of empires was this:
Typically, throughout history, when the food:peasant ratio went too low for more than simply one crop cycle, one kingdom would invade another. In medieval Christendom, populations were held in check by numerous abstinent periods, which, combined with common sleeping areas, held birthrates in check among the peasantry. If the population still grew too swiftly, the religious estate offered plenty of food and reasonable comfort without reproduction.
This system collapsed during the plagues, when the population fell so low that the religious festivals seemed pointless, and so few educated people joined the religious estate that the vast land holdings of the religious estate seemed wasteful.