Which of these rules are still in implementation in this day and age?
A couple of these rules are still implemented around the world. In a lot of our classes, we talk about body language and costumes, what the actors should or could wear. Most countries, especially in Singapore, their audience is very conservative or at least their government would like the population to be so there are a lot of restrictions on appropriations in films based on their audience and target location. Based on this, ratings of the film in different countries vary greatly on what they think is appropriate and whether or not they believe the younger generation should be allowed to view.
How would the implementation of such rules change the portrayal of art?
Crime and immorality would never be allowed to be portrayed in a positive light as it could influence someone to do something bad but with all of these restrictions, action movies become very bland and repetitive and almost easy to call what shall happen next. The joker has been one of the first movies I have seen where it is really more of the perspective of the villain vs the hero.
Do these rules work in preserving the morality of society?
There will always be other ways that an audience and society can get a negative influence.
Can rules and art co-exist?
To an extent yes but you need to have that natural flow to some art and by having certain rules it restricts that flow greatly, caught by the neck. Some say they need rules to follow to make films or art look appealing and others say the complete opposite.
There are lots of films that are told from the perspective of the villain. One of the first films that really did it well is In Cold Blood (1967) which was an adaptation of a Truman Capote Novel. The Film Noir movement of the 50s and the rise of the anti-hero portrayal allowed this film and others such as Scarface and Dog Day Afternoon, to take the perspective of the villain. Public Enemies with Johnny Depp playing John Dillinger is a contemporary example of this.