Because it's not and you're full of shit.
Crime in youth is way, way, way, way down. High school graduation rate is way, way, way up.
What a moronic lie to tell. You should be ashamed of yourself for making up such bullshit out of thin air.
This lie is necessary in order to prop up the belief system of a large portion of our society.
See, if society IS better today - in real, measurable statistics - than it was 40 years ago, then much of the clamoring about the
moral decay of the republic becomes hollow. So it is essential to claim that events - crime, graduation rates, teen pregnancy, etc. - are worse today, even if they're better.
The United States of the '70s and '80s was a lawless, crime-ridden hellscape compared to the country today.