I really worry about the impact on my teen dd’s eyes and general health
There has never been any causation found to screen time and these harms.
There is a correlation between outdoor daylight time and myopia (which obviously kids who are always on screens would not be getting, but a kid who spends 10 hours on screens and 2 hours a day outdoors is more protected than a kid who spends 2 hours on screens and 10 hours playing with dolls and no time outdoors)
And there is a correlation with sedentarism, both more time seated, and not getting the required exercise. Remember that's a minimum of 1 hour a day exercise, and long periods of sitting should always be broken up.
If you can do those things, any amount of screen time has not been shown to be harmful in any study yet.