the only reason why MK Ultra was discovered was through a cache of just under 100k files that were supposed to be destroyed but ended up being found on accident. This forced the CIA to shut it down after it being unknown to the public for over 30 years. aka we don't really know how far back it goes and most likely will never understand the entirety of its reach. The Water gate scandal had everyone in the CIA destroying everything under strict rules if my memory serves correct.
Where would the conspiracy therory on MK Ultra be? That the CIA has a research programm using drugs and psychology to find a truth serum against spies of the Soviet Union? And people said this is a conspiracy theory and then the Church commission proofed it not to be one?
How would the Phoenix Program also be a conspiracy theory?
Where is the difference between a secret government agency program and a conspiracy?
https://en.wikipedia.org/wiki/Project_MKUltra