Gameplay Tags Blueprint usable

Hello,
I love the Gameplay Tags and their functionalities. The practice of having hardcoded (String) tags is very bad and the probability to mistype at least once is very high so I really love the Gameplay Tags since they provide an easy-to-use tag-system with no chance for mistyping.

Every Actor has a function “Actor has tag” by default. You can do that for Gameplay Tags as well, the function is called “Has Matching Gameplay Tag” and compare the Actor’s Gameplay Tags with another Gameplay Tag.
However, you need to implement an interface called UGameplayTagAssetInterface that the Actor can be compared with Gameplay Tags. Unfortunately, this Interface is marked as NotImplementableInBlueprints - WHY? Why can I only use it in C++?

It would be a HUGE benefit to be able to use it in an upcoming release, maybe even for 5.1.

Sure, I can give an Actor gameplay tags by my own and use the function “Matches Any Tags”, it is a function that doesn’t need the implemented interface since I can provide the tags and this function compares them - but I need a way to get those tags from my Actor.
Let’s say I overlap with an Actor, then it would be very convinient to say “Has Matching Gameplay Tag → Character.Enemy” instead of having to check if it has the (string) tag “Enemy” (or make other checks, for example by the class).