Meaningful to whom? You're using 'meaningful' like it had was some objective, measurable thing, whilst it is actually a value judgement. This is what I have been saying all along, agency is subjective because what is 'meaningful' is subjective.
From a player perspective, perhaps.
A GM, however, has enough information to figure it out objectively...
You know whether or not you had two separate options ready, or just one that you quantum responsed.
You know as a GM whether or not you had two (or more) outcomes before the roll, and whether or not the roll actually mattered.
And you know whether or not you gave the players information about the various options that is valid for making informed decisions either on which choice to pick, or whether or not to roll.
Unless the GM goes the extra (burning) mile¹ and states "If you fail you will (insert short version of failure result)"... in which case, while the surprise factor is reduced, the meaingfulness of the rolls, at least, is assured.
And if one goes the apocalytic mile² instead, player agency is (theoretically³) assured unless and until the player either does something that triggers a move, does something asinine (which includes narrating things that violate the setting), or the players as a whole stop generating story motion and/or GM amusement.
It's not like the GM can't use those techniques in more traditional rulesets, either, and put heavy amounts of agency — considerably more, at times, than Gygax would, based upon his Dragon columns — and get some interesting results. In my Elestrial Concordat campaign (using Mongoose Traveller 1E), all sensor rolls were to pick what was there, not to see if anything was in fact out there. This lead to some nifty XD threats in Jumpspace. I won't run Traveller again that way — too much chance for out of genre ideas — but I might in fantasy of some stripe.
Notes:
1: As in Burning Wheel, where the standard for an action is the player is required to state the method
AND the intended effect. The GM then offers up a fail condition, if one is interesting, or says "yes." If a fail condition, the GM then sets the difficulty and the player his/her/xer dice pool.
2: As in Apocalypse World, where the GM isn't supposed to actually do direct actions until a move goes wrong... or the story stagnates a bit, or
that guy attempts to pull a very out-of-setting or past reasonable capability fast one... Instead, they're supposed to ask questions that help the players drive the story. At least, that's the ideal.
3: we all know that sometimes, reality is less than ideal theoretical results. Especially when humans are involved.