One theory is that a lot of the buzz is just some former intel officers like Luis Elizondo of To the Stars trying to get donations. Grusch happens to be a former intel officer. Who knows? maybe they are disgruntled or want to cash in on their former jobs. Although Grusch does not appear to be involved with an NGO that does this kind of thing, maybe he will release a book soon? This is speculation.

Another is that maybe we are in something of a Cold War right now, as predicated by the weather balloon incident, but the USG wants to keep it secret. If people spot UAPs there is a counter narrative now about aliens that drowns out talk of war. It seems like knowing we were being spied on could cause reactions the government would rather not deal with.

et cetera...