The New York City arts organization has launched a festival of autism-friendly programming, including “small-batch” theater. About four years ago, Russell Granet, Lincoln Center’s arts executive, had an eye-opening conversation with a parent that ended up changing the direction of Lincoln Center’s programming. The parent lamented that she could no longer take her family to the world-class performing arts center in New York City because the shows there were too overwhelming for her child, who is on the autism spectrum.