I would acknowledge that. But it might be overrated. There might be a counter-example there. In any event, science doesn't probe happiness itself. It merely supplies you with tools that can aid your happiness, but often the same tools make you miserable.
Drugs can ease pain, but they can also produce an alley full of drug addicts.
Somebody might think about this for a minute and say, Okay, there are some other things that are really important that are physical. Pleasure makes people happy. Pleasure is something entirely physical. I'm sorry, but that's mistaken. Not only is pleasure not entirely physical, it is not at all physical.