Earlier quoted context omitted.
For the article in question, they are banning someone who blatantly committed criminal acts against the state. Literally an attempt by the president to overthrow the government. Treason is a crime that's enforceable with a death penalty.
For someone with such deep knowledge of the law you surely must know that a person can be considered a criminal only after being convicted by a court. So in this case the punishment was carried out based on allegations only.
You're absolutely correct that in the US no one may be punished by the state without due process. But Stripe isn't a government and refusing to do business with someone doesn't require a criminal trial.
Or are you claiming that Stripe cannot choose its customers unless a court has convicted that customer of a crime?