Good read, but one major thing instantly comes to mind.
Yes, small teams make for fast teams, but what happens when your dev in a team of 2 leaves? Your 10x speed drops to 0x, or you pull in another 10x dev and they drop to 4x or less (because we all know the seriousness of switching costs).
It may take a while to find an interview a replacement since you need someone that is great, not good.
I prefer to work in smaller teams at smaller companies, but can see why larger companies are large. They care more about consistency than max speed.