GDP in "real dollars" is irrelevant here. Any such measurement can't correspond to something meaningful.

Rather "annual calories from agriculture per capita" would reveal much more of the reasons behind this and other upheavals in Europe during the period.

There were climate/weather changes (not well understood or appropriate to research in light of current climate changes) in Europe during 1500-1850, which caused starvation, upheavals, migrations, wars, and so on. They did not affect all areas simultaneously in the same way.