Since I have not one, but two subjective questions (one of which was closed, and one of which was not) on SharePoint Overflow, I thought I'd share my thoughts :).
The problem seems to be around the wording of the question (ie using "best" or "worthwhile") moreso than the content of the question. Both questions have quite a few views and both have excellent and objective answers that would legitimately be of use to someone working on SharePoint. For that matter... as SharePoint consultants, the answer is almost always a subjective "it depends", and that is not a bad thing.
I agree that I picked poor wording for the questions. If the first question (What is the best tool for reading ULS logs?) had been re-written as "How can I troubleshoot correlation ID's in my ULS Logs?", it would probably not have raised any eyebrows. The second question (Are SharePoint certifications worthwhile?) is one that is asked and answered (specific to those domains) on several of the other Stack Exchange sites that I visit (pm.stackexchange, Serverfault, Stackoverflow), and are consistently highly-viewed and objectively answered.
I am totally against questions that are legitimately argumentative ("Why does SharePoint suck more than my_favorite_CMS?"), but I don't think the above questions are argumentative or overly subjective. If there is an opportunity for a moderator to just re-write the title to remove subjectivity, I think that's a better approach than closing such questions.
Just my 2 cents :)