Headlines about the Argentine debt default are somewhat misleading. If you read the entire Bloomberg article, you'll see that Argentina is able and willing to pay its other bondholders, and has deposited sufficient funds to do so with a trustee bank.
A U.S judge has blocked Argentina doing so unless they first pay off the holdout owners of bonds in default. If they do so, they'd have to go back and pay the other 90+% of defaulted bondholders the full amount as well.
The 90+% took a haircut, they settled for something less than 100% of what they were owed. The 90+% would have to receive the full amount originally owed if any holdouts receive the full amount. Argentina is either unwilling or unable to pay all holders 100% of what they were owed.
This mess could have been avoided by paying their bond debts in full when they came due. In the interim, Argentina will have difficulty borrowing at rates they're willing to pay.
