The government has been studying UFO's at the highest levels since at least 1947 and likely prior. You don't study something closely for 7 decades and not learn anything.
https://www.cia.gov/library/center-for-the-study-of-intellig...
https://www.cia.gov/library/center-for-the-study-of-intellig...
I do believe that any qualified historian of science could point out to you topics in linguistics (origin of language), psychology (nature of consciousness), astrophysics (what's inside a black hole, if anything), and many other topics where more than 7 decades have gone by, with lots of smart people studying a topic, and yet at the end of that much time practically nothing has been learned.
The government has been studying UFOs for 7 decades
==> The government has learned something
==> The government has acquired alien technology
Check out Philip J Corso or Robert Salas, but there are , many, many others who have blown the whistle including Walter Haut the public affairs officer during the Roswell crash (and recovery).
https://en.wikipedia.org/wiki/The_Day_After_Roswell
https://www.disclose.tv/capt-robert-salas-ufos-shut-down-nuc...