Looking back to the big push to HMO’s and primary care physicians, a lot of people viewed it as freedom of choice being lost. And having to have things approved by your PCP led to problems. This is not first hand experience since I was in my twenties at the time and healthy. I’m just relaying the sentiments of several coworkers.
But I think it’s things like this that have people concerned - the potential for government oversight to complicate and delay things, and decrease the quality of the care/care providers.