One missing information about all other objects after the 1st balloon is their nature and speed. Why should they keep this information classified? It's like the objects were a lot more complex than a balloon (propelled drones?), with varying attitude and speed and telling what they were doing when they were detected would reveal what they were doing while still undetected, that is, giving information on military capabilities to the Chinese.
Pure speculation on my part of course, still I'm puzzled by all this secrecy.
Any information given to the public (you) will also seen by the enemy (whoever it is)
It's like when America used to go on television during the Iraq/Afghanistan wars and announce where they were going to do surprise attacks and then get butthurt when they got wiped out.
Letting the enemy keep guessing about how much you know, and how much you recovered, forces them to waste time and resources trying to figure it out. It's likely to promote additional missions which in turn will give you an indication of how valuable they consider whatever it was, and if you have intelligence on who's contacting who, it also tells you who the operation might have been under and thus the overall disposition of their government.
There's endless good reasons in the intelligence business to keep things secret.
