How are you still not getting this? It has nothing to do with when he signed up. It has to do with when he had the procedures.
If he had had the procedure in the 1970s and hadn’t paid his bills yet, should the ACA have retroactively covered him?
Yes, insurance companies are shitty, but you can’t blame the ACA for not being magical and wiping out all debts that ever existed in history before it came into effect. There has to be a cut-off date where it starts coming into effect. That date was January 1st of this year.
You can blame Congress for not passing it a year earlier, sure, but there will always be people who still had debts from before the law. And you can bemoan that it’s not single-payer system, but that still wouldn’t have wiped out historical debts.