About 50,000 doe and youth hunters hunt for a few days in the "early season". About 650,000 hunt in October and November, that's where the pressure comes from. More bowhunters hang stands and dump bait in September than actually deer hunt in September. That's the human pressure that tamps deer movement. Don't forget the new scent pressure of trail cams.
After lots of habitat work love and turning my entire property from diminishing deer sightings, open older growth forest to dense young 2nd growth that deer now flock to, I passed 6 bucks on opening day of firearms season and my land is in one of the heaviest pressured parts of northern Michigan.
I shot a buck yesterday, while sitting with my 6 year old daughter. She was a super trooper with air temps at 17, a 20mph wind dumping 3" of snow and in a hilltop blind (windy) we call "Weatherby Ridge".
I think the biggest confusion for some is they haunt old hunting grounds and familiar stand sites of old memories, instead of either managing private grounds, moving sites or moving towards public lands recently disturbed via timbering. Deer require edge and new growth. Find it or create it. If not, you're not going to see deer like in the days of a Michigan herd of 2,000,000 deer when anyone with 5 acres of sand had deer all over the place as long as they dumped a bag of corn out. Even if you have 5-10 acres, improve it or lose it. If you have 20 or 40, you can do a lot more improvement that you think, by just a chainsaw and sapling plantings.
Deer hunting is a lot like trout fishing. The river changes every year. One has options, they can fish a hole that trout no longer frequent due to habitat changes, they can move to another hole or they can improve the habitat of the stream.
I know the owner of a local auto repair shop. Deer/auto accidents are still very frequent. There is no conspiracy. The deer just moved from where many are used to sitting. While some area's have declines in accidents, there were still roughly 45,000-60,000 claimed deer auto accidents last year. And that's just the accidents that cause enough damage to make a claim.
A common fault is, if one hunts now fairly open, mature woods with a mix of mature hardwoods and little understory that held lots of deer 20 years ago, they're missing the point that the deer have moved to "younger" forest habitat that looks like those woods did 20 years ago.
It's kinda like going to Detroit and looking for a $25 an hour job. While they can still exist, they aren't due to turning a bolt, they exist by creating a web page or reading a CAT scan. Things and times always change. There's lots of great hunting in Michigan and it's only going to get better. The key is to understand what changes need to be made take advantage of that great hunting. If one isn't willing to make adjustments, the future may not be as bright.