PSA: I baked hockey pucks for 2 years because I packed my flour with the measuring cup
My aunt watched me scoop flour straight from the bag last Thanksgiving and asked why I wasnt fluffing it with a spoon first, and that one tip fixed every dry cake I made in 2 years of Sunday baking.
Did you ever try just weighing it instead? I know the spoon thing works and all, but honestly once I switched to a kitchen scale I stopped worrying about how I scoop the flour at all. A cup of flour can weigh anywhere from 4 to 6 ounces depending on how packed it is, so fluffing helps but you're still guessing unless you weigh it. Maybe it's just me but the scale fixed my dry cakes way faster than changing my scooping ever did.