The article talks a lot about EU competition laws and what I got from a brief scan wasn't that Wikileaks was claiming Visa & Mastercard had to do business with

The article talks a lot about EU competition laws and what I got from a brief scan wasn't that Wikileaks was claiming Visa & Mastercard had to do business with them but that they coordinated financial blockade by the two biggest payment processing companies amounted to some sort of collusion. So it's not necessarily what they did, but how they did it.