Actually, if you look at the image, Slack is beholden to US law, export regulations and economic sanctions - companies doing business with countries they shouldn't are in big trouble. See also: Huawei, who despite sanctions continued to do business with Iran, which caused the US to give them a huge fine. I don't know how that works given how Huawei is a Chinese company, but there you go.
To clarify: private companies are not and should not be above the law.