The court isn't saying "preserve this data forever and ever and compromise everyone's privacy," they're saying "preserve this data for the purposes of this court while we perform an investigation."

IMO, the NYT has a very good argument here that the only way to determine the scope of the copyright infringement is to analyze requests and responses made by every single customer. Like I said in my original comment, the remedies for copyright infringement are on a per-infringement basis. E.g., everytime someone on LimeWire downloads Song 2 by Blur from your PC, you've committed one instance of copyright infringement. My interpretation is that NYT wants the court to find out how many times customers have received ChatGPT responses that include verbatim New York Times content.