How many engineers do you think are actually managed by LF? From my understanding, the majority of engineers contributing to Linux are on the payroll of other companies like Google.

I would say even less because you have to take into account all the costs of hosting, dev machines, laptops, testing, travel etc. $1 million for such huge project is peanuts this days.

more like 3-5 given people who can manage this kind of code base are of high value.