Weren't the crew already doomed before WAU

[cantremember]

Yeah but it's the WAU making copies that inspired her, and also allowed Catherine to learn about how to do it herself for her ark in the first place.

Without the WAU going berserk, they wouldn't have had gained the knowledge to create the Ark and would have been doomed to whither over time.

So in a way, although the WAU caused them a lot of suffering, in the end it's what enabled them to have their Ark live on in space. Which to me is quite ironic, the WAU largely contributed and acted as a catalyst with the copy procedure, in causing humanity to be preserved in some way.

So although quite indirectly and probably unknowingly, it did succeed in its ultimate task.