Yoshi in an interview mentioned; "With the Trust system, these players can experience the story of Final Fantasy XIV and learn party dynamics by playing with their favorite NPCs. Then, once they feel ready, they can shift into playing with other people. The challenge level of content using Trusts will steadily rise, and so it will not always be the easiest option to play with them exclusively."
Seems odd if they restrict it to Shadowbringer content if part of the purpose is to expose players to party dynamics. By the time a player gets to Shadowbringer content if they haven't been exposed to and learned party dynamics something has functionally gone awry.
