Those usually aren't the same people. In my (albeit limited) experience, the AP-heavy kids were prepared to do at least acceptably at college. It's the ones who squeak through without AP classes (which are optional) that aren't well prepared.
Plus, remember that our society tells kids that you must go to college to be successful, so many 18 year olds go to college, not because they want to, but because it is expected. Meanwhile, other kids go into a service industry such as HVAC, auto mechanics, plumbing, or electricity and end up making significantly more money than those who drop out of college and serve french fries.
In the case of my daughter the AP classes didn’t make that much of difference. We had strongly encouraged to take the English and History AP class so she could get English out of the way; She passed the class and did well enough on the AP exam to get credit for both English 101 and History 101. But when she took English 102 at the college that fall, she downright struggled along with her other classes. Maybe it was first semester stress, but she came right out and said college wasn’t turning out quite like she had expected it to and wasn’t sure of herself anymore, despite the fact of having a couple of college classes under her belt.
I’m pleased to say she did find her way before it was too late that fall and she just finished her sophmore year getting a 3.7 this last semester. Our oldest son is up and coming and wants to go to college and I’d love for him to go, but our biggest concern is on how well he’ll do as he has Asperger’s so it’s somewhat of a challenge to figure how to make him best prepared but we are confident he can succeed.