While changes to insect populations are a thing, it could be in part that your car is more aerodynamic than the ones you rode in as a kid. That would reduce bug impacts, and increase fuel efficiency.
I agree with another poster that it's likely aerodynamics.
But, it reminded me of an incident when I was a kid. In a minivan, all windows open, highway speeds. Driver hit a swarm of bees. I've never seen a density of bees like it. Made the windshield opaque for many seconds of wipers and spray, and the number of bees that came through the side windows to be smashed against the back windows and luggage was shocking.
I don't know anything about swarming behavior, and it's been years since I thought about that incident. Thanks for the memory!
It depends on where you live, but winter and flying insects are terms mutually exclusive normally. Many species adapt their cycles to pass winter in form of eggs/larvae or just hibernate in a quiet place. Some migrate. Most adults just die.
Over the winter holidays, I drove 9 hours and don’t believe a single bug was in my windshield after that long drive.
I don’t know what’s happening with bugs but could it be related?