Did UFOs make it clear they don’t want us to progress technologically too much?

Do any UFOlogists think the “whistleblowers” in recent years is govt attempt to prepare the public in case some the Malaysian flight or another abduction/death was real and will eventually get publicly known anyway? What’s the point in hiding UFOs from the public out of security concerns to hide it from the UFOs themselves when the leaks already suggest the govt retrieved and reverse engineered crafts?