[Before asking this question here on Meta, I did search for duplicates. There are similar questions, but I found no exact duplicates. If they do exist, please direct me to them, and I will delete this question. I did find this: "This question appears to be off topic because it is better asked on ELL." It provides excellent discussion, but I'm still looking for consensus or a more concrete answer. I find that I'm tending more often to use comments to answer questions because I am concerned that if I go ahead and provide a formal answer, more established users may downvote it because the question itself was too simple and not appropriate for ELU.
I just commented on this new question: "What's the difference in (sic) could and will in the future?" The author of the question provided a sentence using each word and asked about the difference in meaning. The sentences were "Will it happen?" and "Could it happen?"
My first step was to search for a duplicate question. I found questions about differences between future and conditional verb forms, but nothing that referred specifically to "could" used in this way.
My next step was to answer the question. Instead of writing an answer, I chose simply to write a comment, because I had a doubt as to whether the question was off-topic for ELU.
I'm rather new to the site and have this doubt fairly often. Are there any objective criteria I should be using to decide whether to go ahead and answer fairly simple questions like this one?