When you want to automaticlly generate a list from tags you have to use multiple complicated tags to create sub-catagories.
Take a magic system that divides spells by tier and elements. Sure now you want all tier 1 fire elment spells. That is easy the tag could be #Tier1Fire.
However once the posibility for dual elements are introduced things become more complicated. Now we have to decide a defined order of elements e.g. #Tier1FireWater or #Tier1WaterFire. This is still manegable if you write down your tagging conventions.
It becomes impossible to do without multiple tags if you decide to do it by saying the tier does not apply to the whole spell but per element, e.g. #Fire1Water2. At this point you could not search out the tier 2 water component at all
I suggested the same not long ago and it was rejected then. But I still think the feature would be extremely useful. Because it was rejected then, I don't put more than 1 coin to it though.