In some cases, I think these sorts of expenditures sit on a slightly blurry boundary: when used to buff an action resolution roll, in circumstances where the action is being made by the character whose player spends the point, I often see them as corresponding to trying harder, and that is very close to being something the character can do, although because it is about emotion and urgency it may not be quite under the character's control.However, spending fate points in Fate or Inspiration in D&D 5e lies outside of decisions that the character can do or make in the fiction, but these are things that the player can do when playing the game, but they would be excluded as player agency if you talked about player agency strictly in terms of the in-fiction agency of the character.
But a barbarian's rage would probably live in the same space, at least sometimes, I think. And bardic inspiration is also a bit weird - presumably the bard is trying to gee up their friends all the time, and it's not quite clear what is different either in the bard or in the friend when an inspiration die is spent.
Edwards frames the ingame/metagame boundary as turning on "who is considered to "spend" them - character or player." I think that some of these sorts of mechanics are deliberately presented to make that a bit ambiguous. Like bardic inspiration. Or even 5e D&D hit dice.