Yeah, Bitfinex and Tether won't have anything to worry about...
...as long as they don't want to have USD denominated bank accounts, or transact with USD, or do business with people with USD denominated bank accounts. Which, of course, they do. If you touch the US financial system in any way, or if any of your counterparties do, or if your counterparties want to have other counterparties that do, then you need to care deeply about what the US federal government and the NY state government think.
Gemini and Coinbase are on the forefront of legitimizing cryptos. They go out of their way to cooperate with American authorities, which is a good move for their business model. Contrast this with a crypto exchange based outside of the US that would loose their clientele if they worked with the American government in any way. Why you ask? Do research about Americans trying to open bank accounts in Europe. Basically under the new laws banks in Europe prefer to reject Americans rather than try and go through all the extra reporting involved.
Most crypto is traded outside of the US though; most of the volume is on Binance and Bitmex. In this sense they cut themselves off from many customers. The advantage of their business model seems to be that with less competition from other US-law-abiding exchanges (because there are so few of them), they can charge much higher fees: Coinbase fees are higher than most large non-US exchanges, and Gemini fees are insane, something like 1% per trade.
Actually most don't. The IRS released statistics a couple of years ago, it seems like the number was low 3 figures who actually reported though I don't remember exactly.
The article says after being banned from doing business in New York, they opened up offshore shell companies to open accounts with NY banks, engaged accounting firms in NY, and dealt directly with NY based investors.
That is pretty solidly doing business in New York.
Most of their executives live in NY. Most of their largest investors live in NY. They assisted investors in creating offshore business entities. They used NY accounting firms.
They could simply arrest employees, freeze their assets, and charge them with crimes. Then freeze assets and charge banks that did business with them, similar for investors.
If it wasn't a company largely run by and for Americans living in New York it would be a different story.
"Tether and Bitfinex also allegedly opened accounts at several New York banks, housed most of their senior executives in the city, and engaged New York based accounting firms for audits. "
...as long as they don't want to have USD denominated bank accounts, or transact with USD, or do business with people with USD denominated bank accounts. Which, of course, they do. If you touch the US financial system in any way, or if any of your counterparties do, or if your counterparties want to have other counterparties that do, then you need to care deeply about what the US federal government and the NY state government think.