Retired US Army Colonel says secret UFO projects should be made public by October 2030 - to beat America's rivals and get ahead of a 'catastrophic' leak
I'm assuming catastrophic leak would mean the US government doesn't get to control the narrative. I'm not sure how the leak would be catastrophic for the average citizen.
That is probably what is going on. The motive of doing their duty of disclosing intentionally according to a plan makes more sense then "cashing in" or "driven by conscience". Either of those are likely for isolated individuals but at this scale it's probably a psyop to prep for an eventual revelation (or something!).
General public perception of the government isn't exactly rosy as it is. It's hard to imagine what sort of leak would be catastrophic in terms of tanking public perception.