Most kids don't know how to self-regulate screen time. Saying "no screen time" for an arbitrarily large amount of time seems anathema to growing up today, but saying "no more than N hours a day" (where N depends on age and kid and what the kid does for the time) seems quite reasonable.

This isn't just about screen time imho, it's about ensuring balance when kids don't yet know what's best for them. A "healthy relationship" doesn't mean "free to do as much of it as they want to the detriment of other aspects of being a healthy human being."

Anecdote: My best friend growing up was super into soccer. So much so that other parts of his life were suffering and he had little life outside of it. So his parents set a weekly limit on the number of hours he could practice and play. He hated it at the time. But during his down time he found programming and now he's a programmer and soccer isn't nearly that important to him anymore.