Big companies like Facebook and Google already employ a ton of people whose full time job is OSS work. At Google, the number is definitely larger than 100. And this isn't just mid-level people. There are principal engineers doing this stuff.

This does aggravate some of the OSS community, however. Calls of "Google is taking over C++" or "Embrace, Extend, Extinguish" are common from the community. This represents a big problem: the community does not agree about what future they want to build.