I don't think that the term 'young adult' means an adult that is young, is see it as more 'adult in training' which is exactly how we should see these youngsters. Secondary school is in the business of taking in children and turning out people who are old enough to get a job, live alone and get married. In short giving them the skills to survive in the real world.
So, no seeker, I don't think you should expect your DD to act like an adult all the time, just perhaps some of the time so that when she is an adult it doesn't come as a surprise what you actually do as a mother.
I live with people who were excessively mothered (not to say that you do but the mothers of these boys did) and one of them didn't even know how to switch on the oven when I met him.
However, I may completely change my mind when I have DCs of this age
Some responsibilites of a adult, secondary school pupils can meet. They can cook a meal once a week, they can do a few loads of laundry etc. I believe that if a youngster is capable of doing some of the things I would expect an adult to do then they are entitled some portion of the respect I would offer a full-grown adult.
You never know, you might be given more respect when your DD realises just how much effort it is to keep everything together. I know that when I left home I dearly wished Mum was around to clean the toilet take care of me again.