You'll notice that you earn 'interest' on your old questions and answers. As time passes and links to information build up, people will find your posts through searching. At that point, what you wrote will either help them or it won't. Sometimes, older posts earn negative interest.
Closed questions are still eligible for voting for a very good reason, they're still visible. We want people casting votes based purely on the usefulness, accuracy and quality of a post. The fact that the title says
[closed] shouldn't influence that.
I like questions like the one you wrote, they just don't fit well in the Q&A format that is Stack Overflow. People are probably reacting to that while turning your question up in a search when researching a specific problem.
Closed questions naturally decay over time, as high rep users cast deletion votes. If you're really concerned that the question isn't really useful and want to speed that process along, flag it for moderator attention. Unfortunately, you can't immediately delete it yourself, the question has up-voted answers. It will take several additional votes to delete before it actually happens, or a binding moderator vote.
But, remember - the chief concern here is the usefulness of the question in question, not the cost of the down votes.