It was basically this:
1) Parents don't understand a child's emotional needs. Children need a foundation of love, which at an early age basically means attention from and interaction with caregivers.
2) Modern parents, especially pronounced starting with baby boomers, often feel they didn't get enough love and support from their parents. So they lavish their children with praise – frequently instead of focused attention – and think they're doing a good job.
3) This creates children who commingle love with achievement. That is, their parents love them because of their supposed achievements, and thus, if they're not achieving things, they aren't worthy of love. So children simultaneously have inflated egos but also very insecure egos. (This also ties into the whole idea that you should praise a child's effort, not their intelligence.)
That's all very abstract though. He gave a bunch of examples, but only one has stuck with me. Let's say your three year old comes to you with a drawing. Unless she's a prodigy, that drawing is going to be objectively bad, mostly squiggles with maybe a shape or two.
How most modern parents respond:
Parent: Good job! This is such a pretty drawing. I like how you used different colors. That's a great circle. You're a good drawer. Can you go draw me a square now?
Parent then goes back to watching TV, which would be a smartphone in an updated example.
How a parent should respond:
Parent: Thank you for showing me your drawing. I like how you used different colors and only drew on the paper. (legitimate praise is fine). What's this? (points to circle blob)
Kid: A horse.
Parent: Oh, a horse. Cool. Does she have a name? (or Is the horse happy today? Can he run fast? whatever. The point is to engage in open ended questions that show you care and let the kid drive the conversation, somewhat.)
Kid: His name is cow.
Parent: A horse named cow, how silly.
And so on.
Anyway, I'm sure people would have problems with my sample good response too, and I'm probably misremembering the details. I'm also not sure the baby boomer stuff is totally accurate. But the overall idea is to give attention and focused interaction, not undue praise, and that makes a ton of sense to me.
Edited for typos and formatting.