The Black Death killed as high proportion of the population of England, as in France. Yet it didn’t result in the collapse of the English state. Instead, the king and nobility adapted — by invading France, gaining peasants there to compensate for the ones they lost in England to the plague, and by generally exporting surplus elites and thus instability across the Channel. It worked well for a century (but then the French put their house in order and kicked out the English in 1453, after which England immediately collapsed into its own disintegrative crisis, the Wars of the Roses).