If I wanted to ask a question about bash, should I also add the tag shell? Similarly, if I were to ask a question about gnome, should I also add the tag linux? python and python-3.x? Maybe there could be something automatic done about this?
But we need to be careful and proactive, since gnome isn't necessarily related to linux, and there are many tags which could be located in multiple places in the hierarchy (none come to mind at the moment).