Even if the technology was there for it (which it very well could be, the govt is usually 10 years ahead of the public technology wise), there just doesn't seem like a big enough payoff to risk getting exposed just to have one of these senile fucks not trip over their own words during a briefing. Maybe the CIA has some deepfakes put aside for rainy days of national leaders stepping down to ease up their coups, but I doubt anything's being rolled out for that sort of thing