I doubt that AA has shut down most of the AA accounts which have had a history of 2 or more AA card sign-up bonuses credited.

Of the dozens of people whom I personally know to have 2 or more AA bank cards and asked, none of them have found their AA accounts shutdown for having multiple AA bank card sign up bonuses credited to an AA account. Is it possible that some, most or all of them have had their account shutdown and don’t know about it? Perhaps, but I doubt it.

What I am very curious to know is which Member of the US Congress has had the most AA bank card SUB miles credited to their AA account. I have no doubt that there are at least a few of them who have had at least 3 AA bank cards in their name at some point in time.