I think theme is a poor way to convey a concept. Not only is it easily open to misinterpretation it also focuses the attention on determining what exactly the theme is rather than if the idea had any merit in the first place. For instance we are all about to embark on a conversation of how FF shows "In the end, anyone who tries to grab Ultimate Power just ends up wrecking tit for everyone else, and outright destroys their humanity" when in reality it is just a story someone wrote to show whatever the hell they wanted, completely groundless in any actual real world fact. Thematic study is essentially the triumph of emotional opinion forming over ruling reasoning.
(Yes that is right, I am sidetracking and I don't care.)