As the old saying goes:Do not judge a book by its cover,your suggestion I'm afraid is not(never)gonna be implemented
Topics of threads do not determine the quality/usefulness of a thread..

A thread can have a terrible topic but entail a worthwhile content
While some could have an attractive topic(that entices one to open them), but with terrible content

And it only takes about a second to open a thread,and another to close the thread if you find it unhelpful