There’s a very simple reason for that. The show centers on a 9-year-old actor (Iain Armitage) and features his twin sister and teenage brother. “It seemed like the more appropriate way for them to do the best work was in a closed setting,” said executive producer Chuck Lorre.
The new series is very much like “The Wonder Years”; it’s about a young boy and his family, and the adult version of the boy serves as the series narrator. “Young Sheldon” wis narrated by older Sheldon (Jim Parsons, who has played the character on “Big Bang” for a decade).