Tony Vargas
Legend
The difference between a general combat option and granting a player agency with a resource is pretty significant. Obviously, one component of it is relative exclusivity. Choosing to do something anyone could have done is not that big a deal. Another is how it's resolved. Improvisation, for instance, is a very poor source of player agency, because it's really all in the DM's court, and 5e all but defaults to that, being very DM-empowering. A standard combat option (I'm trying to think of one other than attack) has more agency, since the player can probably expect the basic rules to be followed, though, again, anyone could have done it & anything unique/interesting that might happen as a result is probably up to the DM. A resource with explicit effects, like using a slot to cast fireball, OTOH, is higher-agency: it's dramatic, it's not something just anyone could have done, and it's a meaningful choice to use it or not, because it's a resource that must be managed.Or martial maneuvers like grappling, sundering, disarming, dirty trick, repositioning, and the like. Explain the difference.
The difference in caster balance between 3e or 4e and 5e would be more nearly relevant, but OK, regardless of what you think about a particular edition:The only difference between 4E and 3E is caster balance, not the ability of the player to take control of the narrative.
The player with a wildly overpowered caster is going to exercise more control over the narrative. Not just directly, because his decisions matter more than any other players, not just in concept since his spells twist the reality of the narrative, but indirectly, because the DM must shape the situations, story, and campaign around challenging and limiting that character.