My mother was abusive. The helicopter parent idea, and its general acceptance allowed her to blend right in with real parents. She cloaked extraordinarily controlling behavior in the clothes of helicopter parenting which has made me extremely sour towards both that idea and the 'tiger mother' idea.
The reality from my perspective is, constantly having someone looking over your shoulder does breed anxiety. You are after all being watched, and often criticized. Further this attitude of parenting keeps the kids from learning life skills and independence, which keeps them dependent. Helicopter parents then use that to justify their control. This behavior also breeds a feeling of helplessness, as you are aware you lack skills, but also feel you have so little control because of all the scrutiny and constant following orders, that you can't do anything. I can easily see how this leads to low self worth and depression.