When a question is marked as being Purim Torah, is it okay to respond with a serious answer, such as here?
(I don't think the post you link to in the question is a good example of what you're asking about, inasmuch as its author says, in a comment there, that it's meant as a joke. In any event:)
No, a serious answer to a Purim Torah question is not addressing the question as asked (viz with the PTIJ disclaimer) or as intended. Thus, it's not an answer.