So, there's a genuine diversity problem, but the panel make-ups are merely reflecting the supply-side diversity problem, rather than a selection problem.
Reading this article did make me ponder that question further, but these topics are sufficiently niche and the relevant communities sufficiently small that I'm still happy that the lack of diversity on the planned panel is due to a real lack of diversity.
I'm now the BDFL delegate for the in-work PEPs related to packaging, so if I'm not aware of someone working on something related to packaging, they're far enough away from getting anything integrated back into the standard library to make what they're working on off-topic for the upcoming panel.