Every kid is different, so while I understand where you are coming from, IMO I dont think you can generalize it with such a broad brush.
My son is 7, and has been sitting in a stand with me since he was 3. Everytime I've been to the lease the past two years to check cameras, fill feeders, build pens, hang stands, clear lanes, and shed hunting, he has come along. He has learned about habitat, rubs/scrapes, why dad keeps checking the wind, tracking and cleaning a deer, and pulls out his youth bow every time I practice. I am picking him up a tenpoint crossbow this week (bow only lease). Plan is to let him become proficient and let him try to stick a pig late spring. Next year, if hes still putting in all the work and I get to keep teaching him and spending time in the great outdoors, you better believe it's going to be my mission to put him in position to shoot his first deer.