And the boomer generation were called entitled, lazy, selfish by their parent's generation too. Think about the attitudes of the war generation to the hippies, recreational drugs etc.

This shitting on the next generation thing has been going on for a long time.

There's solid evidence going back 150 years of older generations complaining about school kids being undisciplined, not respecting their teachers ("not like back when I was at school"), and some slightly more anecdotal evidence going back some 2000 years of the same.

We always find it hard to reconcile the negative aspects of our old behaviour with our current mindset, and it's way easier to just reduce in our minds the severity or scope of our actions. We learn from our mistakes, and try to make them seem as small as possible in our minds.