Money can't buy happiness? That's just wishful thinking
theguardian.com
theguardian.com
If you have those other things, some money can make it a lot nicer. Example:
Living alone in a city with highly paid contractors and nearly zero social life is not going to be "happiness" for most people.
Then again, a couple living on one average income would definitely have an easier (and that usually means happier) life with extra money.
Think of it like this: Life is a pot of water. Money is salt and/or pepper. All the other nice things in your life (relationships, friends, family, sports, hobbies, etc) are the meat & vegetables.
You can make a soup with just water, meat and vegetables, but its a shit load easier with a little salt & pepper.
Water with salt and pepper is not soup.
Also, poor people are not unhappy people. We all know how to have fun, minus those who don't.
Anxiety is the enemy though, and with a significant amount of our population either debt riddled, on prescription meds, or living paycheck loan to paycheck loan, it's no question many are unhappy.