As a new user, if my question is labeled "homework" in a comment, I might feel accused that I am using StackExchange to cheat in my school work. In many cases, that is probably a good description of what is going on, but in many other cases, this will probably feel like a wrong accusation to the OP. There are many other scenarios where someone asks for the result of a calculation without showing their effort to solve the problem.
To someone who frequently answers questions, labeling a question as "homework" probably means something slightly different - that the OP has not done their homework in posting the question. Expectations are to check whether a similar question has already been asked, typing up the problem rather than posting a picture of it, giving some background (where is the question coming from, what is the level of the answer requested), and - maybe most important - documenting the OP's thoughts and perhaps struggles with the question. The expectations are reasonable - a well-researched and written question will have a greater chance of getting a useful answer, useful to the OP and to the larger community.
So maybe instead of the comment "This is a homework question", maybe the more useful comment would be "You need to do your homework before posting a question", with a link to the existing guide on how to ask great questions.