Birding, silent book club, Mahjong and more: America's meetup explosion

Young people raised on swiping, DMing and streaming are doing something bold: going out. Why it matters: Amid a loneliness epidemic, millennials and Gen Zers are craving IRL connection — enough to show up for meetups built around activities once considered solitary, or "grandma hobbies." The latest: They're leaving the house to play chess, birdwatch and read in silence together. "It's very easy to sit inside and rot just by yourself," Cole Robinson, president of the Audubon on Campus Trinity…