Can't just past Presidents and Vice Presidents brief the current ones with ALL they know about the phenomenon?

Just seen the recent comments by VP Vance where he says he is "obsessed" with the stuff but seems very uncertain what exactly is it as if he still has no clue after a year in office... at first this looks funny, but there seems to be serious NO communication between current and past office holders on this stuff, like every new office holder have to start exactly from ZERO.. Just why don't they round up all the past Presidents and VPs and even CIA heads, Secretaries, etc, etc, and get briefed...