[ ENDING SPOILERS ]Ending Spoilers
I think the worst thing Joel did was killing the three doctors (possibly 1 who knew what he was doing and two assistants). New doctors can't be made easily in this world now if at all. I assume that people could learn a bit by spending years studying medical books left behind in med school. You would have to clear it of infected and form a community there though. So not likely and the ability of the new doctors wouldn't be as good. Ellie could always go back and have the surgery done once shes lived a full life and is ready to die. I also assume that she can't be the only immune person. I'm sure that someone else who is immune will be born eventually. Just kinda hard to know if your immune or not without getting bitten and surviving the encounter with the infected.
A doctor loyal to a warring faction that ended many lives by stirring up shit in and stealing resources from the few remaining relatively safe havens, just because they want to be in power; a doctor that was willing to kill a 14-year old kid for the highly improbable chance of discovering a cure that would solve nothing even in the best case scenario. As far as Joel was concerned, this doctor was just another hunter, killing others for his own gain; just another soldier, fighting in a pointless power struggle that would only lead to more death and destruction and suffering.
When he waved his scalpel at Joel, he sealed his own fate.
There is no black and white here, only grey.
When he waved his scalpel at Joel, he sealed his own fate.
There is no black and white here, only grey.