If there’s only one human player left in a game does that give immediate victory to that person regardless of how strong the AI opponents are? Or does the human still have to capture the required number of stars?

Sometimes if you make enough progress in the game, then hit shortcut key “L” to see the Leaderboard, and there you can find the button “Accept Victory”.

I’ve always had to get to more stars than any of the other empires, excepting the players who have afk’d.