Josh Ginter asks about The Last Jedi:

But seriously, what were they thinking with that Canto Bight story arc?

Poe couldn’t grow as a commander if he didn’t have a pointless mission that endangered everyone under his leadership. Fin and Rose couldn’t become closer without danger.

Somewhere some book on how to write a story said growth comes from conflict and they made conflict up that did nothing about the main storyline because ¯_(ツ)_/¯