Glee was a massive worldwide phenomenon when it first aired in 2009. Their cover songs were on the Billboard 200, their cover of "Don't Stop Believin'" (https://en.wikipedia.org/wiki/Don%27t_Stop_Believin%27#Glee_cast_version) became a classic, and the entire original main cast (https://www.lipstickalley.com/threads/who-from-glee-is-gonna-be-the-breakout-star-if-theres-gonna-be-one.5273447/) became names overnight. Now everyone from the original cast are just working actors.