Each Lemmy community has its own rules, just as each subreddit does. They’re generally posted in the community’s sidebar. Your post breaks rules #1 & #3 of !asklemmy@lemmy.ml. Don’t flog yourself over it though. For some reason c/asklemmy’s rules get abused the most, because a lot of people treat it as a catch-all community.
One good place for this post would have been !lemmy@lemmy.ml: “Everything about Lemmy; bugs, gripes, praises, and advocacy.”. But again, don’t sweat it.
It’s worth noting also that each Lemmy instance has its own instance-wide rules, which are usually posted on their home page sidebar. Which means every post is subject to two sets of rules: the instance’s and the community’s. That may seem onerous at first, but after a while you get the hang of it and internalize the rules of the places you frequent.