Sheldon emerged as the breakout character of The Big Bang Theory, overshadowing the romantic storyline between Penny and Leonard. However, his inconsistent character traits led to episodes that were less favored par fans.
The Big Bang Theory had already explored the theme of reluctant parenthood seven years prior with Bernadette, who initially did not want children but later became pregnant.
Leonard's departure creates an opportunity for Penny's comeback in The Big Bang Theory spinoff universe. With Johnny Galecki retiring, Leonard's return post-The Big Bang Theory seems highly unlikely.
