>Everyone was working their land for sustenance, and the rent-seeking nobility extracted some percent of production because that's what there was to extract

Until the black death came in the 1300's and killed an estimated 30–60% of Europe's population, and now the nobility had nobody to rent seek or even to work their land.

So then, for the first time ever, the surviving workers gained bargaining power as landowners (lords) competed for labor, leading to high cash wages, better working conditions, and more freedom for peasants, because the feudal lords hadn't yet figured out how to replace the peasants with slaves, H1-Bs and illegals from across the planet.

So according to history, including your post-WW1 example, the only times peasants gained bargaining power was when millions of them died through world wars and global pestilence.

Looking at recent unfolding history, "There's something very familiar about all this" -Biff Tannen