It would be a net benefit for the organisation.
If shunning stopped it’s true that some JWs would leave as a result, but many more would stay, it would foster an environment for openness and discussion, some of the wackier doctrines like 1914 would be dropped, and those who do feel the need to leave wouldn’t harbour the same resentment or bitterness that the current shunning policy causes. They may keep on good terms with JWs, turn up for the memorial sometimes, retain normal memories of JW life involving good and bad. JWs would be known as a peace community that truly values family and kindness in fulfilling their commitment to Bible principes.
Stopping shunning is a win for everyone.