I don't know the fine details of this report, but I suspect that most doctoral dissertations include some language found elsewhere. The PhD is typically an academic's first "published" work, and most of us necessarily rely on our supervisor for guidance and approval. https://www.nytimes.com/2023/12/20/us/harvard-claudine-gay-plagiarism.html
@KeithDevlin I believe the real accusation is about lack of attribution more than simply using others' work.
Some use of established language is natural, but the key is that it has to be properly attributed, and it's claimed that the president didn't do that.
@KeithDevlin Yeah from what I've been hearing there has been some talk about advisors and the dissertation committee needing to answer some questions about the accusations.
I would say that the student still needs to bear primary responsibility, but the department also has its own responsibilities to answer for here.