Re: #10, #11, #13
The K-12 schools are not necessarily worse overall than they were decades ago (and the kids now are not breathing fumes from leaded gasoline), though they may be worse in some places but better in other places due to local conditions and policy.
But expectations for high school graduates are much higher. Decades ago, opportunities for a high school graduate to get a job and get on-the-job training to a career were more common. Now, employers want entry level employees to be educated, trained, certified, and/or licensed at their own (or previous employer’s) expense. Such education, training, certification, and/or licensing commonly requires some college education (not necessarily a bachelor’s degree; college being inclusive of any post high school education). So someone who is “not college material” or whose position in the birth lottery makes whatever post high school education that makes good use of his/her potential unaffordable may be very limited in his/her career path, and may become a burden on others.