There were way, way, way more bugs. Yesterday I spent about 12 hours on the highway, and I didn't need to pull over to clean my windshield once. 20-30 years ago my windshield and headlights would be completely plastered after a few hours.
10 trillion members as late as 1875. Soon after, their population rapidly declined, with the last recorded sighting in 1902, and the species formally declared extinct in 2014.