My father told me of this. When he was a kid in Illinois right after WW-1. He said is was devastating and had every one scared to death.
Back in the 1970s a doctor said he was not worried about a flu epidemic like 1918. He said most of the people back then died of the resulting pneumonia and we today have antibiotics to stop that which they did not have back in 1918.
My Great Grandfather got it and nearly died, ironically after returning home from, and surviving WWI.
This is true but the 20th century I think totalitarian government made up a lot of the difference.
My father remembered everyone in his family being sick, but no one died. He said it wasn’t much fin with no running water in the house and no washing machine to help with the clean up.