Motivated by Glorfindel's last meta question, I checked the tag design-decisions as well. It is currently used for only 21 questions.
However, I think half of the on-topic questions on this site fall into the category of making some design decisions. So the tag seems to be too unspecific to be useful, and I wonder if it should be removed, too?
For some of those questions, it may make sense to replace the tag by the design tag?