My understanding is that you want to minimise the leakage of warm moist air from the living space into the colder back part of the insulation. Otherwise if the lower part of the insulation encounters room air with a dew point higher than the temperature of that outer part of insulation, then you will get dew.
You definitely do want the space under the floor ventilated though. If this is decent and the leakage of air from above is minimal, I think it will be fine whatever. Because any moisture will be transported out from below - that is, after all, the point of your breathable membrane.
I'm planning to do similarly for one floor in ours, but at it is probably a project for 2025 rather than 2024.