Is there a general mechanism to review and revise existing tags? I'm noticing that there are many tags for specific data structures within specific languages; wouldn't it make sense to coalesce all those into a few, general tags for that language? Ultimately, if you tag your question as
c++_unique_ptr, you're almost surely going to tag it as c++ as well.
By not offering too many specific tags we encourage people to add all the appropriate general tags without getting bogged down. And reversely it is already the case that lots of lesser-quality questions with general tags are lacking the specific tags that would apply, but end up getting answered anyway.
Removing overly specific tags is one way to clean up. Another way that comes to mind is to de-separate version-specific tags (if that makes sense), but I have no opinion on whether version-specific tags are currently useful. Finally, there are some bogus tags like templates which isn't helping anyone because it subsumes Perl HTML templates and C++ templates. If the tag can't be used meaningfully, do we need it?
Enough with the ranting; the main question is whether there's any mechanized, general process to prune the SO tag soup, and if anyone feels that pruning would be desirable.