I don't know if they can just drop the shunning policy and not be consequences for WT. It would be like opening the gates of the compound so people could come and go as they please. Shunning damages relationships sometimes irevocably. Would those that have been deeply hurt by the shunning even want to talk to their JW relatives and friends again?
What would be the alternative to a shunning policy for rule-lovers like JWs a non-shunning policy? Is it realistic to expect that people you discarded will just start talking to you again after years of persona non grata. Years you will never get back when you burnt those bridges.
Man what a can of worms would that open up amongst the congregations. I mean it would be nice to think if they just dropped shunning as an official policy everyone would play nice but somehow I don't think so.
I feel like even if they gave it up officially it would still be used as weapon on a personal level by many members. Face it there are some people who just like to use the silent treatment to get back at someone and blank people they don't like. It's actually harder to force people to talk to one another than it is to get them to not talk to someone as shunning only takes one party whereas talking takes two.
Conclusion : WT will give it up officially when it's in their best interest to do so, then and only then.