To be clear, I am 100% in agreement with you. Most mobile games (and honestly, most pc games at this point with their item and resource gathering mechanics; and I am absolutely talking about MMO's - there's a reason many many many franchises are working toward a multi-player experience instead of focusing on the single player game) aren't supposed to be 'fun'. They're supposed to be addictive, and I believe it is a real problem, especially for kids growing up learning that a dopamine hit is just one iphone game away.
Anyway, though, I guess my point is - it's all semantics. When you say, it's not 'fun', it's just a dopamine rush, developers and sales people can say that's just the same thing. They can argue that people wouldn't play unless they received some kind of value out of it.
To be honest, I've forgotten where I started with all this, other than to say - when you have to split hairs on the definition, it leaves room for people to interpret their own meaning and ignore nuance. Therefore, this is an argument that people don't want to hear, engage with, or consider, I believe.
So what I am saying is gamers have mostly forgotten what it is to have fun in games. Playing around with cheese wheels in Skyrim is different from grinding a character to game breaking power and killing everything in one hit. Challenges based in getting better at the mechanics are different than challenges based on pure time investment.
IMO the three pillars of a great game are entertainment, fun/joy aka playing, and dopamine rushes. Portal 1 was a standout for having all three, but it’s hard to pull off.
MMO’s basic gameplay without leveling, item drops, or any form of progression have some fun aspects. But, they need to tell players to collect 50 rat tails because otherwise players wouldn’t.
Mobile games have distilled this down even further, with the minimum possible amount of actual gameplay possible.