I was thinking the same thing, why have the company in the Caymans, when you can have the company and the bank account in the US, much easier to open bank account in the US for US company (which is still not super easy if the owner is a non-US person but doable).
In short and generally speaking, US gets information about its citizens from everyone︀ but gives information to no one. So, US is something like super offshore heaven if︁ you are not an US person.