Ah, the never ending discussion about songwriting rules. Maybe formulas or guidelines would be a better name. Or, even recipe would work. What ever the nomenclature, I enjoy sitting quietly listening to banter about acceptable and non acceptable uses of
verses, choruses, bridges, intros, outros, and middle eights. And of course, melody mistakes.

I have looked high and low and never found the published rule book. Where do you read the rules?

If you listen to songs across a wide spectrum of styles and years,
you will find similarities and differences.

If a rule book was written from dissecting all top 40 songs since the birth of radio and records, it would be thick and all inclusive.
Let me clarify, it would be thick from listing all forms that have been used by top 40 songs. I don't think one rule would emerge from a strictly empirical study.

So, where did the rules come from?