As an "elder millennial", I too, saw this happen. I grew up in a very middle class home. About the only thing we didn't regularly do from the list in the OP, was modest vacations.

My dad was a teacher.

We didn't have anything overly special, but we had what we needed and we were not struggling. I have two siblings, and the entire family was a family of five. My mother did not have a job throughout my childhood and well after my teenage years, and I'm the youngest.

Now, I can't fathom having a kid. I can barely pay to keep myself alive.