In a post on their official blog, Respawn Entertainment confirmed that new maps and modes will not be hidden in a Season Pass. Respawn first announced plans to do this earlier this year, claiming that cosmetic item purchases are projected to be enough to cover the costs of ongoing game support.
“This means once you’ve purchased Titanfall 2, your investment includes a full single-player campaign, the full multiplayer maps and modes, and long-term support with no hidden costs” says the post, “You can pre-order the game to play 3 days early, but it will never cost you extra”.
This policy is very fair to the players, limiting paid content to cosmetic items while keeping gameplay-essential elements like maps and game modes free for all who paid for the game.