The disclosure is the psy-op.
The government never stopped developing advanced, physics-bending technology after the Manhattan project. The problem they ran into is that anti-gravity, faster than light travel, zero point energy, etc... would upset many of the pillars driving the civilization. The oligarchs who control the world would have been put out.
They invented the story of “UFOs” so that the engineers and physicists would continue working on the tech and keep it a secret. If they thought the tech they were working on was from a UFO and they were sworn to secrecy, they wouldn’t feel bad keeping it from the masses.
Remember the idea of “mass hysteria” if the existence of UFOs were to be revealed? That was a psy-op against the scientists.
I knew a guy that built high-tech gravity meters used in geology investigations. He told me once that he had been out of town working for the military as their long range missiles weren’t operating the way they had planned. (They take into account the large-scale gravity anomalies when going over mountain ranges, etc.)
He said he was trying to determine if there was “anti-gravity” - just like a magnetic field has a positive and negative force.
They had him down in a deep mine, and then up on a tall tower at the site. He said the tower was too tall and narrow and unstable, it swayed too much to get decent gravity measurements. But - I thought it interesting that the government was interested in the possibility of anti-gravity. This would have been back in the 1980’s.