Adam Mosseri, the head of the Instagram team, recently revealed that Instagram is currently testing the ability for users to share Stories with specific groups of people, similar to Facebook Lists. This new feature allows users to limit their sharing settings to a smaller, more defined audience, expanding on the current Close Friends option. By adding custom-defined subgroups, users will have even more control over their privacy settings.
Mosseri announced the testing of this feature through his broadcast, and asked his followers if they would use it. Therefore, it is still uncertain whether the List feature will be widely rolled out or not.
TLDR: Instagram is testing a new feature that will allow users to share Stories with specific groups of people, similar to Facebook Lists. This feature aims to give users more control over their privacy settings. However, it is still unknown if and when this feature will be available to all users. (50 words)