I'm sure Colin's results can be reproduced, but it will take some effort. Colin has been doing a lot of work so that Firecracker can boot FreeBSD -- see https://www.daemonology.net/blog/2022-10-18-FreeBSD-Firecrac... for an introduction -- and that is not yet all available in Firecracker "out of the box."
From the article, Colin Percival on how Linux does as well. Impressive (though would be good to see other benchmarks to corroborate Colin's).
(Which is an HN comment actually: https://news.ycombinator.com/item?id=37205578.)