But I maintain that in the illustrated case - where you want to get all the different independent values and then combine them at the end - it's actually less ergonomic to do it the wrong way with .then(...) than it is to do it the right way.

Most ergonomic IMO is:

const getPeople = async () => (await Promise.all(...)).flat()

Without await this would be

const getPeople = () => Promise.all(...).then(arrs => arrs.flat())

The difference is slight to be sure, but I usually prefer the await approach.