I think rural seemed lower because of poor record keeping and contact. My maternal grandmother survived it while losing 3 family members. They were in the mountains on the VA/W.VA border.
Aside to that, I’d be curious as to how people alive now who survived it look/are. She turned 100 in December and she is in outlier good shape for that age.
My wife’s late father said his grandmother told him about entire family’s being wiped out in a few days time in the hollers of eastern Kentucky. They were fine one day and three days later small to large families all dead. Said it roared through the hollers like wild fire.