Light gathering in M43 vs FF

There are a lot of nonsensical responses on this forum. The only reason I'm singling you out is because you actually put yours in the subject line.

F1.4 on MFT does in fact give you the same exposure (i.e. light density or light/mm^2) as F1.4 on FF. So, why are you still dead wrong? Because exposure is absolutely meaningless in cross-format comparisons. The light density alone is absolutely irrelevant when comparing M43 and FF. The only thing that matters is the total light (of which exposure is a factor).

I've explained how to calculate total light in another post in this thread.