While it is true that strict education has failed and it is not necessary to be very strict in educating children, it is also important to emphasize that it is wrong to let children do whatever they want. In fact, an excessively permissive approach towards children is very problematic for their growth.
On the one hand, we can say that the permissive model certainly represented a logical reaction of condemnation to the strict model of the past. On the other hand, the absence of rules does not allow the child to acquire the social norms that are indispensable for adapting to the world around them and reaching their highest levels of personal fulfillment.
The famous American pediatrician Benjamin Spock was among the first to promote permissive education; however, through the numerous criticisms that came to his method, Spock later realized that this approach needed to be revised. Indeed, it was equally unsuccessful as the strict and severe approach of the past.
I can easily empathize with children who were immersed in that reality until the 1960s/1970s, growing up with the fear of threats and even physical repercussions. So, I can humanly understand that the wave of protest of those years wanted to destroy everything that was seen as oppressive. The rules were considered as such, even though they were vital for the sustenance of society.
Children need clear rules and limits in addition to affection, reassurance, and trust to grow up solid. The two things together allow the child to acquire the autonomy and sense of responsibility indispensable for personal growth.
The lack of rules, on the other hand, can create in children a deep sense of insecurity, as they do not have precise reference points to orient themselves in the world. In many cases, the absence of rules that we see in some families creates in children a strong sense of omnipotence; however, this does not allow children to develop adequate adaptability and can send them into crisis when they are forced to make sacrifices.
The concepts of right and wrong, good and evil, and more generally, the moral development of the child pass through good adaptation to society.