Because we're lazy (aka human beings).
When they were much younger, I used to tell my kids that people are ignorant, lazy, self-centered, and rude. They hated this and were sure I was wrong. "Who hurt you, Dad?"
Now that they're older, they've learned that their old many was (SHOCK!!!) right all along.
And I've realized that three of the "variables" in my "equation" can actually be simplified.
Being ignorant is the result of being too LAZY to learn, read, question, etc.
Being self-centered is being too LAZY to care about or to act on behalf of others.
And being rude is being too LAZY to avoid unnecessarily giving offense by being ignorant or indifferent to social conventions.
So it all comes down to lazy, really.
We'll generally continue to drown in unnecessary, unsupportable, crippling debt, wildly overvalue shiny, new, unproven things, spend, spend, spend when money is free or nearly free, ignoring the inevitable inflation hangover, overreact and overcomplicate our legal systems, and ignore climate change until we have absolutely no other alternative or until we extinguish ourselves.
'Cause that's what we do and have always done.
Have a blessed day!