I think you nailed it right there. By no means was I any brighter when I was a kid. BUT, this isn't a question of smart/stupid. I think the key here is the question of idle hands.
I never had the problem of going to bed and not crashing from exhaustion. Daily. I remember replacing a roof (with the family) well before being a teenager. Mowing yards from before I can remember (did I get 50c or a $1?, and I always cut the widow next door's yard for free). If it was bad weather I cleaned the house. School work was a priority. Playing a little ball with the neighborhood kids. Working the garden (3-4 acres of 'garden'). My parents didn't have to tell me to go to bed, I was joyful when I could stop. 9pm was wonderful, bedtime.
Today's kids are spoiled beyond measure. Not just that they never get the belt, but they have no purpose. What 'jobs' do most kids have today? Mom & dad hustle nonstop to 'provide'. Why lots leave lots of that work to the kids? I remember we had a near-white carpet through the house, and the kids were responsible for vacuuming it every week and other times if it got dirty. I know so many friends with kids where the kids have near-zero 'chores'.
Every kid should have (during school year) at least 2 hours per day of household chores. And off season at least 3 hours/day if they are pursuing other activities (mowing yards to make a few $). Use their mowing money to pay for their 'benefits': starting with their phone. Let them learn that everything has a cost and appreciate how much work it takes to pay for those things. Start young, chores to match their abilities. And any parent that doesn't and instead whines that they can't make their kids do anything are bad parents, period.
If kids had a sense of purpose, guided activities to stay busy, and appreciated the value of things, there wouldn't be time for stupidity like eating tide pods.
OK, ending the rant...