Good Subjective, Bad Subjective is the canonical blog post in this situation. Subjectivity by itself is not a bad thing; unreasonable subjectivity is. The ideal "Good Subjective" question lends itself to answers that are backed up with something - reasoning, logic, a solid explanation. We deal with the same thing on Worldbuilding. I once explained our application of the Good Subjective policy as follows:
- It's fine to have questions that are a bit subjective or opinionated . . .
- . . . but answers to those questions must be supported in some way - they can't just be pure opinions.
You should be able to constructively, objectively (paradoxically!) say why an answer works (or doesn't work). That is, you should be able to point to X, Y, and Z, things that make the answer good or bad. That's why we try to close questions that ask things like "What color would make my humanoids the most beautiful?" You can't really objectively support an answer to that, can you?
Alternatively, as the help center puts it,
Some subjective questions are allowed, but “subjective” does not mean “anything goes”. All subjective questions are expected to be constructive. What does that mean? Constructive subjective questions:
- inspire answers that explain “why” and “how”
- tend to have long, not short, answers
- have a constructive, fair, and impartial tone
- invite sharing experiences over opinions
- insist that opinion be backed up with facts and references
- are more than just mindless social fun
We need to take this thing on a case-by-case basis. As Hotkeys said, "Should I do [X]?" questions aren't always overly opinion-based (but they sure can be!). I'm not comfortable with blanket-banning them, or, conversely, saying that this sort of question is always okay.
In the same vein, a question like
I have X and Y feature in my conlang, and I have noticed that they cause Z problem. What can I do to fix this?
might be too broad - a different issue than subjectivity - or it might be okay. Again, this is a case-by-case decision.