Have you heard of the "Rat Park" experiment?
Scientists, when studying addiction, put rats in cages and gave them a choice between water laced with drugs (heroin or cocaine or whatever) and water not laced with anything. The rats all got hopelessly addicted and most died of overdose. "Drugs cause addiction." So the scientists concluded.
But there were some problems with that theory. Old people get hip replacements and take heavy opioids for a while, but the rate of addiction is quite low. In the Vietnam war, American soldiers were all very addicted (mostly to heroin) and experts worried that when the war ended and the soldiers returned, we'd have an epidemic of heroin addiction here, but it didn't really happen that way.
Someone got the bright idea to try another experiment. He got rats and divided them into two groups. One, as a control, he did exactly what was done in the first experiment. Cages plus laced and unlaced water. Unsurprisingly, the same result. For the other group, he made a rat paradise. "Rat Park" as he called it. Real grass, toys they could play with, food they liked, social interaction with other rats, but he still offered the same choice of laced and unlaced water. The rats in Rat Park tried the laced water (after all they didn't really even know it was anything but regular water at first), but virtually none showed any signs of addiction.
Turns out conditions make a big difference to things like addiction. But the real clincher? He took the addicted "control" rats and put them in Rat Park and they voluntarily detoxed.
The conclusion? Addiction isn't so much about "drugs" as it is about unfulfilled needs. Of course rats in solitary confinement in drab gray cages with crappy food are going to do the only thing within reach that has any chance of making them feel good. The "selfish" thing, if you will. But rats with fulfilled needs are a different story.
This isn't a story about rats or about (only) addiction. People in good circumstances -- people whose needs are met -- have a capacity for being "good" that people with unfulfilled basic needs don't. (Abraham Maslow, anyone?) Now, look around you. Is the world as it is today set up to fulfill people's needs or keep them wanting? (Maslow estimated -- very generously, I think -- that 3% of the population had their basic needs fulfilled and were "self-actualized.") Capitalism is predicated on the idea that want is bottomless. (It's basic economics to pretend satiety doesn't exist.) Every company out there with a solution has its fingers in whatever they can do to cause the very problem they purport to solve. The news is all about creating addictive FUD. Humans are kinda fucked right now. Of course in this situation folks are going to be selfish.
(Mind you, the richest folks aren't necessarily the ones whose needs are best met. Just think whether Musk comes across as someone who isn't deeply unsatisfied.)
Yes, the vast majority of people are selfish assholes. But it doesn't have to be that way. It's not human nature. This is what happens when you put humans in very unnatural situations.