It can be hard to figure out exactly what is outlawed with banking interactions. It seems a lot of the KYC/AML stuff is based on industry best practices and guidelines. There's no law you need a state ID with address to open a bank account, but when I tried to open up a bank account without an address I found it basically impossible. The bank will then cite that these practices are what they're held to as law, because the law itself is vague and relies on more nebulous customs.
So what is called "guidelines" one day becomes legally binding later with no act of congress.
Unfortunately there's a massive swath of mere guidelines and regulation that end up having legal binding. For instance, a Navy sailor was recently sent to jail for 20 years for having gun parts that were cut up the wrong way, the "wrong way" being the right way with previous mere guidance and the wrong way apparently being the fact that some time since then the guidance changed but not the law.
See this very nice blog-post: https://www.bitsaboutmoney.com/archive/kyc-and-aml-beyond-th...
It explains how KYC and AML law function as a stochastic control on crime. How that is difficult to do through actual laws, and what the downsides of this system are.
That's the whole point. They can't overtly outlaw things because aggrieved parties would sue and win. So they soft outlaw them with expensive record keeping requirements and ambiguity because no business big enough to win but smaller than a giant mega-corp will intentionally risk going toe to toe with the government in court as doing so would likely be financially ruinous.
And even if the government doesn't look like it's disposed to do that in your situation you're still sticking your neck out by deviating from the herd because then you can't screech "standard business practice" when some contrived chain of facts results in you fending off a civil suit for whatever reason.
This isn't just a banking thing or a guns thing, you see examples in every industry once you know the pattern.