Both are right. The older ones with squiggly letters, numbers or that ask you to identify animals or objects were being used to train ai bots.

The ones that ask for crosswalks, bikes, overpass, signs etc are used to train self driving ai.

There’s a somewhat rational theory that Roswell happened because it was the site of the nuclear bomb testings and aliens “only try to contact civs that are at splitting the atom tech level”.

It has some merit to it, but yeah, look at that map. Hardly convincing when looking at the reported sightings.