[JohnBooty]

    The voice was uncanny. Simply hard to listen to, 
    despite being realistic. I mean precisely that: it 
    is cognitively difficult to string together meaning 
    from that voice.

What? According to the information under the linked video,

    In order to protect Gwern's anonymity, I proposed 
    interviewing him in person, and having my friend Chris 
    Painter voice over his words after. This amused him 
    enough that he agreed.

I'm not familiar with the SOTA in AI-generated voices, so I could very well be mistaken.

But it did not sound fake to me, and the linked source indicates that it's a human.

Perhaps it sounds uncanny to you because it's a human reading a transcript of a conversation.... and attempting to make it sound conversational, as if he's not reading a transcript?