Author here. One thing I really enjoy about this team is that we're trying to avoid silos and build a cohesive team that can flex when needed. As Matt mentioned, a number of the boards discussed are a result of someone jumping in and helping where there was a need. The Gemini bring-up board was done before we even had an "official" hardware team.

The official hardware team is about 10 people, but there's another 5-10 people that somewhat overlap.

Several of the boards discussed in the post were designed by people that are nominally on the embedded team, e.g. I designed the Gimletlet NIC and Root-of-Trust-Carrier-Carrier.