1. Feudalism is two incomplete concepts. the first is "feudal pyramid" textbook stuff. that never meaningfully existed as a totalising system anywhere. things like slavery and municipalities coexisted with 'feudal' arrangements. the understanding of feudalism as a pyramid of obligations is based upon the late 18th century France, and it was defined as such to abolish it. the shit about peasants, nobles, and clergy is explicitly the estates general called in 1789, not even necessarily other 'estates general', which was by the way not a universal or very long lived feudal institution.

the second definition of 'feudalism' is a marxist one. this one makes more sense but isnt quite up on the times, particularly with the 'transition' of 'slave' economy to 'feudal' being much murkier than originally thought. another is the assertion that feudalism disincentivises development & improvement---this is demonstrably untrue

2. feudalism ended---on different timeframes in different places--but most dramatically and thoroughly in western europe with the French Revolution