As I understand it, frame gen doesn’t predict frames but interpolates frames. So it doesn’t “look into the future” but inserts frames between those rendered by the game. With the selling point being 30fps could look like 60fps. The reason this works is because “guessing” what those extra frames between existing frames look like is relatively easy. The game has already done all the hard work of figuring out the actual frames, then frame gen uses a faster algorithm to make the I between frames. Because frame gen adds the frames in between the real frames you can feel more input lag.