Some ten or fifteen years ago, Scientific American published an article about the positive correlation of "general intelligence" with virtually every measure of success in life. Like earning enough money to be comfortable, having the emotional intelligence to have a successful marriage, etc.
It's rare to find an objective measure where being stupid is a good thing, unless you're the cop who figured out the criminal mastermind's plan and got assassinated or similar corner cases. Even if you're not in a position to excel you're not going fail and I'd argue it's just as much your objective successes like a steady job and organized life that puts you ahead of the deadbeat drifters when it comes to finding a mate, tests show your EQ can suck despite a high IQ.
Obviously the lack of material goods can cause unhappiness, but most of us have the basic needs covered. The rest is pretty much a state of mind, are you happy? I'd be happier eating junk food if I didn't know all the crap it does to my body. I'd enjoy T&A more if I knew it wasn't a biological preference to easy child birth and ample breast feeding. And it certainly doesn't get better if you end up where it doesn't matter because you and everyone you knew will be dead and building a pyramid for a tomb is just stroking your ego.
I generally find my happiest moments are when I'm too preoccupied or suitably intoxicated not to think too much. Just existing in the moment, feeling good, having fun, enjoying the ride, savoring the taste. If you "pierce the veil" more or less and realize you're playing an RPG to get level+1, skills+1, armor+1, weapons+1 to fight monsters+1 or lather, rinse, repeat what used to be fun just loses all interest. I guess you can call it a more general form of suspension of disbelief, the suspension of further intellectual inquiry. If you're happy, stop thinking. You're only going to ruin it.