I know smartphones can be useful and convenient. When I got my first smartphone, an iPhone 4, I was absolutely flabbergasted by how nice that thing was. I could email, take pictures with a thousand different funky filters, store and listen to my music, and also carry entire (offline) dictionaries in my pocket, which I used (and still use) extensively while reading. But that was a luxury product, and that's how I saw it then. Back then you could buy dumb phones for 30 bucks, get a SIM card off a shelf in any store and use it away anonymously, drug-dealer style, with no need for any sort of registration, and not be called a freak for it. And, at least in Europe, you could do that with an iPhone as well.
Now, even if you could still get a SIM that way (and you can't), you need a million online accounts to manage your life. We now use apps for a million different things, such as hailing a ride or ordering food or managing your finances with your bank. It's no longer simply the case the smartphones are convenient, now it's straightout inconvenient not to use them. And they leak your data and your habits and your location, all the time, to some people you're aware of and to some people you aren't. It's not a case of you being in the driver's seat vs you letting it drive you, it's about who's using your device against your interests behind your back. I guess if you're living in China it's all very clear to you there's nothing you can do about it, and you might as well get whatever device has the better specs for the money, whereas in the west we can complain about it, but realistically there's not much you can do about it either. So pick your poison.
As for the other social and pyschological harms smartphones can bring you, they're really the harms of social media. Smartphones make them easier and more portable, but don't create them.