Neither OP or GP have it right - Fuchsia isn't a "3rd OS", it's a kernel, like Linux, except MIT. Maintenance is most certainly rewarded, at least in the 5 years I've been at Google
"Zircon is the core platform that powers Fuchsia. Zircon is composed of a kernel (source in /zircon/kernel) as well as a small set of userspace services, drivers, and libraries (source in /zircon/system/) necessary for the system to boot, talk to hardware, load userspace processes and run them, etc. Fuchsia builds a much larger OS on top of this foundation."
- Fuchsia Docs, https://fuchsia.dev/fuchsia-src/concepts/kernel
Sometimes they stumble upon something another PA needs, but often it just ends up as a patent or research paper.
Who can divert from Google's massive ad income funnel?
Apple.
Facebook.
(Also maybe several foreign governments' antitrust cases.)
An engineer on your payroll is an engineer not on the competition's payroll.
Guido van Rossum (creator of Python) is a Distinguished Engineer at Microsoft. Before that, he worked at Dropbox.
I get the quarterly check-ins from the "alumni recruiting" team, and can assume Guido does too.