You and others are quite correct and I misspoke: It's hard to experience happiness if you're worried about your basic survival. A few years ago, it was found that an average of $70k in North America was the cut off, where anything above that has little to no impact.
While I stand by the contention that virtually nothing will provide sustainable happiness in the long-term, existential problems (lack of food, shelter, or love) can certainly get in the way.
Likewise, experiencing chronic pain will continue to impact your ability to enjoy life.
But!
The mind does have an incredible ability to adapt. Ask anyone experiencing chronic pain and you'll find they have a higher pain threshold than most. Likewise, those who have been poor their whole lives find poverty to be less traumatic than those who've had a "fall from grace" and have to adapt to sudden poverty. But adapt they will.
The mind is constantly trying to return to the middle. So if you're trying to maximize happiness and minimize suffering, know that you're working against your own biological wiring. Good luck with that!