Are you using his definition of player agency or your own?
Well, Bedrock's definition clearly doesn't include, "The capacity for players to advocate for their character's dramatic needs and have the system and group social contract support that intention, without unilateral imposition on that drive by the GM."
So, sure, if you exclude that proviso, then BRG's games have as much player agency as every RPG game, ever.
And just to be perfectly clear --- I am NOT attacking BRG's playstyle. Hell, I've run multiple campaigns with the intent to run exactly the kind of campaign he's describing---a largely player-driven (as much as possible within the constraints of a "traditional" system, in my case Savage Worlds) "idyllic sandbox."
And having attempted to do that, in my experience it's very hard to consistently frame situations that remain player focused without some additional systematic backing.
And it takes a lot of effort on the part of the GM, and a desire on the part of the GM to nearly fully avoid inserting their own agenda into the mix. Without that level of effort from the GM---especially when using a "traditional" system---it's entirely too easy for "idyllic sandbox" play to devolve into "setting tourism."
And as a player, I am flat-out DONE with setting tourism.
One of the core drives I've had in exploring new avenues for increased player agency is the experience I had 2 years ago in a friend's Savage Worlds campaign, where he ran the game largely as a "tourist setting" for Shaintar. By the end I was pushing against the restraints on agency so hard, it was like I could practically feel the straitjacket.
So what am I really trying to say? I think what I'm saying is that I both appreciate what Bedrockgames is trying to do, while also fully recognizing that there's a blind spot in his preferred playstyle that isn't addressed through any of the "conventional" sandbox techniques he's holding to.