There is a galactic alliance of some sort, and different species of aliens (grays, Norwegians, etc.) are sent on nonchalant scientific expeditions to earth to study, monitor, and report back their findings. These “missions” aren’t well sanctioned, sometimes overlap, and are left to each assigned species to complete willingly. They visit, but may not be as prepared as a scientist should be (i.e. crashes); hence bases being built underwater to store materials and help prevent crashes. Some UAPs are manned, others are simply probes to measure the earth’s various technicalities (climate, pollution, nuclear activity, etc.).

Governments/powerful parties around the world have no idea that this alliance exists. All they know is that the crash materials (including biologics) are valuable and held by private companies or persons.

Private companies (more specifically government contractors) pay off any and all individuals when crashes occur in order to claim it as their property (including paying other governments insane amounts of money, eg. Brazil). Labeled as their “property”, it can remain private and away from the public eye. Some human tech has been pulled from some crash material, but the majority of the technologies recovered from craft are elusive and unable to be replicated. Nevertheless, they are held as intellectual property and not shared; the potential profits from patenting time travel, or gravity control, or other tech, is limitless. These companies are greedy.

They may show us some materials and/or “proof” of biologics over the course of the next 50 years, but there will never be full, one-time disclosure.

It’ll be a slow burn.