Thing 1: Spoilers
I think it's not so hard to handle spoilers in answers to questions. For example this Psycho-Pass s1 question requires s2 to answer, so you can just say
My answer spoils s2.
[insert answer covered in spoiler]
Similar for this Danganronpa s1 question.
I guess the harder issue is spoilers in questions.
Consider an anime X based on manga X. Let's say there's a question about the latest chapter of manga X but then an unwitting user assumes the question is about anime X and opens it. Then the user is spoiled.
I happen to know in other sites like reddit or myanimelist, it is extremely forbidden to put a spoiler in the title. This isn't just for anime but other for other fiction subreddits/forums and even for, like, sports or gaming subreddits/forums. To address the aforementioned case, those sites/forums even go a step further to have people say what exactly is their post about (the anime and if so what season/episode, the manga and if so what chapter/volume, etc)
I think we should say in the title or the beginning of the post what is being referenced. What do you think?
We could go a step further to do like:
If I have a question about the anime X but want to mention a bit of manga X, then I can take 1 of 2 approaches:
Approach 1: Mention at the start the question is about both anime X and manga X and thus have no need to use spoiler tag but this may discourage anime-only fans from reading my question.
Approach 2: Mention at the start the question is about anime X and so my little bit reference to manga X shall use spoiler tag. Thus, I don't discourage anime-only fans from reading. Something like this Kaguya-sama s2 question, which brings up a later manga chapter but in spoiler text.
Thing 2: Clearer or more helpful
I believe this would also make it more convenient for users who might not have otherwise answered. Their 1st question about the post might be 'What episode/season was this again?'