In my experience, many parents are coddling their teenagers somewhat. What teenagers often need is boundaries to their behaviours they can rebel against and a parent who says 'I'm here if you need me, now fuck off and be awesome'.
What many teenagers are getting is parents that are misguidedly ploughing the path for their children's future as a form of misplaced benevolence. In many instances this has resulted in the pathologising of anxiety, a perfectly normal response for a child to have in a novel situation. Rather than teaching kids how to handle stress they are shielded it from it.
My friend, a therapist, was amused to find a mother attempting to muscle her way into her daughter's sessions. Insisting on a joint plan, something her daughter would be able to handle and get on board with. The daughter was 23, my friend was amused because the root cause of the anxiety was also being presented as the cure.
I see a lot of anxious teens... and behind a lot of them are parents who are doing their best but fundamentally misunderstand that children are necessarily malleable by design and more emotionally bulletproof than their parents presume - even if they don't feel that way. Feelings and thoughts aren't the same and we should encourage children to think about why they're anxious, how it can help them, and how best to think their way through it and not just endorse and react to their feelings.
This does also apply to other sections of life - but teenagers give far more credence to their feelings than adults because their brains are restructuring and myelination is still happening. :o)