Valid points, and it isn't a priority I agree. "Nice to have" is a fair categorisation.
It is a pain point for me though, hence the suggestion, and it doesn't feel like a huge thing to implement.
The "adding new tags being infrequent" was poorly explained - what I was trying to say was that the number of times I actually *want* to add a tag is infrequent, the number of times I accidentally add a new tag is significantly more often. Having an "Are you sure" prompt would save me a lot more time than it would waste.
I can only speak from my use case, but don't ask don't get 🙂