Have you read all the laws in your country? Are you aware that there are probably thousands of examples where they've been arbitrarily enforced and put innocent people in prison (or even executed them)? Many of them are just a matter of common sense and yet there's an entire apparatus around them. Does that mean they're silly and useless?
I've never organised a conference, but people who have told me that there's a level of craziness that most attendees or speakers aren't exposed to. I don't know if a code of conduct makes their job easier or not, but your glib dismissal fails to take into account that conference organisers don't enjoy judicial immunity and enforcement of anything -- be it written in a code of conduct or just common sense -- can make them liable for damages. One way to protect yourself is with a system of due process, and some lawyers think that a written code is helpful in establishing due process while others disagree.
Many laws are silly and useless. Many laws are ambiguous. Sometimes you read a law and think you know what it means but it turns out it applies where you don't expect and doesn't apply where you do expect.
The law is complicated and expensive and painful. You need lawyers and judges and juries. People are, as you observe, severely hurt by the law.
These are reasons why we don't need some pseudo sub-law drafted quickly by amateurs. The real law still applies and the fake law is arbitrarily enforced.
Obviously there are pros and cons, but one cannot conclude that one way is worse than another if you only look at the bad outcomes of that one way. You need to compare the overall picture of both ways.
I've never organised a conference, but people who have told me that there's a level of craziness that most attendees or speakers aren't exposed to. I don't know if a code of conduct makes their job easier or not, but your glib dismissal fails to take into account that conference organisers don't enjoy judicial immunity and enforcement of anything -- be it written in a code of conduct or just common sense -- can make them liable for damages. One way to protect yourself is with a system of due process, and some lawyers think that a written code is helpful in establishing due process while others disagree.