> I think you might be mixing up trade imbargo with a sanction

Being employed, or even having been employed, by an entity on the BIS's Entity List will make doing business in U.S. and in U.S. dollars expensive and tedious. At the very least, you will impose ongoing additional costs for every financial institution you interact with.

Of course not, I'm simply pointing out that this certainly places you in the "super high risk" category as far as any KYC procedures go.

Perhaps confusing it with the OFAC list, which is directly about banking and blocking transactions for named entities and individuals.

Not confusing with the OFAC list. Being on any list makes you a toxic customer.

Yes, there are other designations which would carry even worse repercussions.