This topic is rather difficult as it will not offer a clear-cut answer. I believe that it is best to consider a mixture of both styles. It is like many things in psychology, that one side alone is not enough to explain or create a certain outcome (i.e. nature vs. nurture discussions). Children need protection, but I also firmly believe that they need clear borders about what is acceptable behaviour. As parents you do not always have control over role models, as you cannot control the complete environment, so yes you as a parent will sometimes miss something that later needs to be corrected. And other times there are children that will not discuss with you, they will ignore you. So how will you teach them anything? Do not forget children are not fully developed adults. They don't reason the same way as we do. There are things that will have to be the way that the parents set the rules and the children will have to listen and obey, but it does not mean fear needs to be involved.
But sooner or later children have to learn that there are going to be authority figures in their lives that will not discuss anything with them (i.e. work relationships). If they do not learn this while they are children, they will have a hard time to adapt.
Also if the authorial upbringing was so wrong. We wouldn't be here anymore as every human would be damaged goods, and after so many centuries most likely irreversibly damaged.
As for the nanny shows, I think they are c..... They are viewed so we produce them to make money. They vanish as soon as no one watches them anymore and the topic will vanish. And sometimes I think those shows are an insult to psychologists, even if the "nanny's" have a psychology degree.

In the end I think that upbringing should be individually tailored to the child. There is no universal general method of parenting that will fit every child in the same way and help them to develop the best way (which is a discussion in itself as the best development is influenced by culture, society and generations). Parenting will always be a dynamic interaction between two parties. And yes sometimes the parents have to be authorial to teach a child that behaviour has consequences, that are not easy or pleasant. Even if the child is unwilling to understand through words alone. This does not mean I say hit you child or isolate it, but consider nature. No matter how far we humans might develop, in our core and very basic we are animals. Thereby we might consider a few tricks we see in other animals that have worked for centuries and did not harm the children at all. Logically there will always be deviations from the norm or social and cultural standards, but that brings me back to the individually tailored parenting.

Just a few basic thoughts about the discussion of authoritarian or non-authoritarian parenting in psychology 36 years ago and nanny shows today. Balance is the key. Don't worry about the label, worry about your children. Do what is best for them. Or when it comes to punishment, "Punishment should befit the crime" (in relation for a child, so don't go eye for an eye).

Ups. Got a little carried away while writing.