The bug wasn’t exploited by any hackers, and the feature is unavailable on all Apple Watch models running watchOS 5 or later. To exploit it, a user would need to do a series of specific events, and not by accident.
Walkie Talkie will remain unfunctional until Apple pushes a server-side update, or even a software update, to affected Watches. This comes after Apple disabled Group FaceTime Apple disabled Group FaceTime on iOS 12, due to a major bug that could be exploited by anyone. The company’s security processes and implications have been improved after failing to quickly address this.