Well, I will say that a request to preserve potentially relevant evidence is much different from actually obtaining that evidenceEvidence relevant to what exactly? Counselor.
I didn't say that the requests covered relevant evidence. I said potentially relevant evidence. That's a pretty huge difference, and the reason why they could only request preservation rather than production. There's no way to know if they're actually relevant to the subject matter of the investigation unless/until you uncover additional evidence that justifies their production.
In any case, you can quibble over whether the records were even potentially relevant all you wish. The point is that claiming invasion of privacy based solely on an overly broad preservation order is just wrong. The proper objection is that it is too burdensome.