Because it is super-risky to consider these things on their own merits if you are not the kind of person who regularly interacts with judges and juries. Laws are something that are applied within a particular kind of, ah, culture. You have to be familiar with the body of work of that culture and how they will likely interpret the law. Trying to interpret laws in ignorance of that culture is likely to lead to interpretations contrary to those with the power to enforce the laws, and land you in a lot of trouble.
In other words, laws aren't code or mathematics. They're not pure exercises of abstract thought to be considered in isolation. Trying to treat them that way is going to lead to trouble.
Does everyone downvote all medical speculation in the numerous health threads on this site?
No.
It's fine for people to speculate about medical ideas, legal ideas, etc. Especially on a forum like this where there is no pretense that people are offering genuine legal advice.
Personal attacks are not ok on HN. I appreciate your concern for the quality of the site, but doing this is one of the worst ways to destroy itt. So if you'd please review https://news.ycombinator.com/newsguidelines.html and follow the rules when posting here, we'd be grateful.
carbocation is right about the underlying point, btw. This is an internet forum, the purpose is good conversation, and speculation is a normal part of conversation. It can of course be dumb and low-information, but it needn't be.
In other words, laws aren't code or mathematics. They're not pure exercises of abstract thought to be considered in isolation. Trying to treat them that way is going to lead to trouble.