James Poniewozik, writing for The New York Times (gift link):

He didn’t land the pope, but he got a Beatle. He didn’t have a new project to announce, but he left us with a song (in fact two). He didn’t choose to end his show, but he ended it his own weird, wonderful way.

Stephen Colbert hosted his final “Late Show” on Thursday night, completing the story of the TV year’s most notorious and rancorous cancellation. But his final hour-plus — an emotional and delightfully bizarre wake for a comedy institution — turned it into a cancellebration. [...]

In fact, the episode gradually revealed a story arc, more like the closing episode of a surreal comedy than of a talk show.

Series finales are so difficult to do well. I find them compelling even when they fall a little flat. Colbert’s finale last night was just amazingly good. Good and fun and surprising and perfectly on-brand. And what a song to end on. Perfect.