I understand (and respectfully disagree with) your preference for interactive UI over efficiency. As I have said, the grouped tags filter approach can be suitable in some use cases, but surely not all, considering that DT is often used to manage a significantly large number of files. There is a reason we have Google Search, but not something like Google Tags Filter for Web Pages, because the sheer volume of existing webpages makes filtering by tags useless.
Anyway, the workflow that suits your needs is the best one 