Tags are beautiful. They enable a non-hierarchical way of linking elements together so they form a graph. And graphs are beautiful. But they are also messy and bring a whole cohort of problems that you wouldn't have with trees.
The problem with tags is that they are the first and often only metadata available to represent the complex relationships between elements. So everything goes in it: tags for the semantic (ontology is rabbit hole in itself), tags for relations with other items, and not forgetting the tags project management (priorities, people, milestone,...).
Want to empower your tags, for instance adding hierarchy or dynamic tags? Then every tag will get these features and associated problems. A solution would be to have tags of different "types", each processed differently, and migrate the metadata from a "bag of tags" to "a bag of bags of tags". But then tagging wouldn't be as simple writing a name in a field.
The problem with tags is that they are the first and often only metadata available to represent the complex relationships between elements. So everything goes in it: tags for the semantic (ontology is rabbit hole in itself), tags for relations with other items, and not forgetting the tags project management (priorities, people, milestone,...).
Want to empower your tags, for instance adding hierarchy or dynamic tags? Then every tag will get these features and associated problems. A solution would be to have tags of different "types", each processed differently, and migrate the metadata from a "bag of tags" to "a bag of bags of tags". But then tagging wouldn't be as simple writing a name in a field.