Well firstly, specifically in gambling, self-reported statistics from the NCPG indicate that of the 60%-ish of the population that will engage in gambling, about 5-7% develop problems around that gambling. So it isn't 99.9%, it's more like 95%.

Secondly, let's take this out of percentages: That 60%-ish slice is 150 million people, so your conservative 5% number of people who will have problems amounts to 7.5 million people. So like, if you were being a bit hyperbolic but not terribly, you could say your fun hobby of gambling which you do responsibly, is still responsible for 7.5 million people's addiction. Which I agree isn't a reason to BAN it, but I would say is a reason to, I dunno, not make it so you can do it on your phone? Which was the status quo for the majority of the time we've had smartphones. Like a major deterrent to sports gambling being addictive, even where it's permitted, was that you had to actually go to a bookie's and place bets, and collect your winnings there, not just sit on your sofa doing it on your phone.

Thirdly if you want to expand this into video games, I think addiction there is pretty problematic too, and has gotten substantially worse in the last ten years or so, specifically with the advent of micro-transactions. When I was a kiddo if you were "addicted" to something like Grand Theft Auto, the worst thing that would probably happen to you is your parents taking away your XBox and telling you take a fuckin shower and/or go outside. Or coworkers telling you you smelled, if you happened to be older. The worst thing you could say from that era would be something like WoW subscription fees, and while that's definitely ethically gray for me, I think they can make an argument on the fact that you just buying the game can't offset the costs they face in keeping it updated, maintaining the online services to enable it, the moderation of that platform, etc. etc. etc. However modern Gacha games especially have taken a LOT of heat for flagrantly predatory monetization practices that greatly affect people with certain kinds of neurodivergencies, who spend tens of thousands of dollars on them, oftentimes against the wishes of their carers or spouses. That certainly sucks, and I don't think there's any kind of ethical argument one can make in favor of it, it's just straight exploitation of vulnerable people.

TV addiction is gonna be it's own paragraph but most of the people in my parents generation think the Democrats are communists and are so utterly brain-rotted from the idiot box that they can't even answer basic questions about the reality they live in, so I'm gonna say that's kind of "enough said" there.

There's always going to be an element of addiction in anything, you're correct, because addiction is really just getting hooked, to a problematic degree, on the sense of pleasure you get from doing or consuming a thing, and that thing can be basically anything. That said, a whole lot of very large, very valuable businesses, including many that are owned and operated by the State, take advantage of that to push predatory products onto vulnerable populations, and that's kinda fucked, no?