There are lots and lots of rules of storytelling that are good ideas. Things like 'do not do ninja slash'. But these are IRON laws that must NEVER be crossed otherwise you will instantly and totally alienate your intended audience.
In romance, the princess may never die. The prince may die and frequently does. But if you kill off the princess like Babylon 5 did to Talia Winters, then you're sending the message that love is worthless.
In action thrillers, the protagonist may never be overpowered. If they're overpowered compared to the villain then there is no risk or danger, thus there is no thrill or excitement.
In heroic adventures, the protagonist may never be hypocritical in their driving values. The protagonist may be a lying conniving psychopath, but they MAY NOT be a hypocrite. And if a supporting heroic protagonist is hypocritical then the protagonist MUST call them on it. Because tolerating hypocrisy sends the message that principles are worthless and that values are worthless. Imposing one's values on the world is what adventures are about.
In Mysteries ...
In Horror ...
I'm sure these are collected somewhere, and I wouldn't mind knowing about it. I was told two of them without any explanation why they're iron laws. In fact, the cretin who pointed out that "protagonists may never be overpowered" never qualified it as applying only to action-thrillers, so it never seemed like an iron law to me since I hate action thrillers. So I only just figured out that iron laws exist and *why* they exist.