My (unpopular) opinion is that the way it works at the moment is daft. Im fairly sure the system should be used to block communication from players being rude and abusive via chat/voice, not to filter players who want to kill you in Open out of your instance.
verbal/libel abuse it against the rules hence why there is a block feature; people trying to kill you in open regardless of reason or motive isn't and people shouldent be able to use it as such.
There are several other methods in the form of "game modes" to avoid people who want to play their game within the rules that just happens to different from ones own, i don't think the block feature addition needs to be another.
My 2 credits.
My 2 credits worth is that you can use it or not. If you don't like it then don't use it and vice versa but asking for a feature to be removed that you don't use because you don't like it is, if you don't mind me saying so, nonsense.
So you don't use it but others might wish to do so.