People who get addicted to playing the ‘Unity slot machine’ would have just gotten addicted to something else, porn, drugs, real slot machines, online poker, sports betting, etc…
Sure some people may have addictive personalities but by and large these things are designed to get people addicted. Someone who was never addicted to, nor ever would have normally become addicted to anything can become addicted by trying something supposedly benign as a 'game'.
It's relevant because you claimed if these people didn't get sucked into games that they would just be degenerates in other walks of life. I don't think it's all that debatable that people are addicted to their phones. Most people that are addicts wind up there out of casual exposure. And, hey, it's unregulated and the one tech company that has your back is making it so easy to do.
I had an iPhone before IAP. There was a marked shift in the type and quality of games once IAP took hold. I suppose we can argue that the app store was in its infancy, but as a consumer I've never liked IAP. It was pretty clear to me it was a very easy way for company's to not be forthcoming with their pricing. Sometimes they want to exploit the sunk cost fallacy. In the mobile gaming space, it's often more nefarious. And we know it's by design because these companies hire psychologists specifically to find new ways to get people to part with their money.
The fact it's so easy and you never have to open a wallet also makes impulse purchases way more likely. And, unlike physical goods, there's no room for buyer's remorse. No returns, no refunds. You can try to do a chargeback, but say goodbye to the rest of your Apple account and enjoy owning a brick. Sure, for some people making instantaneous digital purchases it's a way to shave 30s off an infrequent activity. For many people it takes away their ability to consciously push back on impulses.
I don't think it's a given these sorts of games would have just happened without Apple making it so easy on devices people are already addicted to. We've had decades of popular video game consoles of all sorts -- computers whose only purpose is to play video games -- and this was not an emergent phenomenon. It seems to be pretty unique to mobile phones. It hasn't stopped game publishers from trying to port similar tactics to consoles, but it also largely hasn't taken root there despite their best efforts.
Undoubtedly, some people spend hundreds on skins and it may not be money they have, but I'd argue even that digital good is better than P2W mechanics like needing to buy hearts just to beat a level. A level that's impossible to beat otherwise, but the game will waste your time and build up your frustration thinking you might be able to do it. I think it's ugly and unethical. Apple makes a boatload of money from it and it's one area where Apple really hasn't stepped in to protect their customers. Meanwhile they've fought hard against alternative app stores and sideloading under the guise of protecting their customers.
FYI, Google's not immune from any of this criticism. They just were followers in the whole thing so I fault Apple. Google failed as a competitor to provide a better alternative and settled into also raking in 30%, enjoying the privilege of a duopoly.
So it’s not clear if it’s a net negative at all.