Your right Alvin...and wrong.
Obviously you came from a family that loved you and were able to teach you the values during the time they had.
Many fine people are born in and grow up in family's that have two working parents. Having one parent at home is not a guarantee that you will turn out properly anymore than saying a child that grows up in a working family is doomed.
If you treated parenting like knife making, it would go something like this;
Many knives are made by people who do not own any power equipment. Many of those are beautiful and useful knives.
Many knifes are made using proper grinders, Etc. Many are beautiful and useful knives.
It's just easier using the power equipment.
Your assertion that working parents only give up 2 1/2 hours is untrue. Using your time line the school is raising your child for the better part of their day.
True they have him or her during that time but any parent that blindly allows the school to teach values or anything other than the three R's, is playing Russian roulette with the child's future.
Parents need to be as active in the school and at times, a genuine pain in the arse, as they are at home. Parenting can't be measured in hours, it is a 24 hour a day job. That job comes ahead of any other job the parents have. Many working Moms and Dads can't make that distinction.
My Mother gave up her teaching job to be home with us. That did not guarantee I never got into trouble. The fact is I did. I spent several years in Military School because of some of my pranks. I was allowed to start College a year early also because of one of my pranks. Thats a long story but it wasn't because I was smarter than anyone else. It was because the school allowed me to use my college credits to complete my high school graduation requirements and the principal felt it was better for the two of us to be separated. (He had no sense of humor

)
But...the bottom line is that my mother was always there to redirect me when I strayed off course. My father was also, but he was a practicing attorney and did not have the time to drop everything and find out what was going on right away.
It's harder to raise children now Alvin. Many of the things I did when I was younger, Like taking Sam Heltzels Johnny house on Halloween, and putting it at the only stoplight in a nearby town, would be a felony now. Back then, everybody got a stern look, made you take it back and laughed like hell when I was out of earshot. Kids can't do that anymore.
It is just easier to have a full time parent. That's not a guarantee, but it is using the right equipment.