Earlier quoted context omitted.
> With 50 or so devs (let's forget for this example about managers, UX researchers and designers, HR, etc.) you'll get maybe a JavaScript VM and a small UX. Safari does those two specific things with a quarter of the number you mentioned. The entire team is nowhere near a thousand people.
Safari runs on 1.5 operating systems and a limited set of hardware.
WebKit runs on macOS, iOS, iPadOS and watchOS across Intel and ARM architectures.
WebKit provides the web views for countless 3rd party apps, including Mail, Calendar, iTunes, etc.
Apple certainly has fewer people who get paid to write code for Safari/WebKit than Google has on Chrome/Blink. I wouldn’t be surprised if Mozilla has more people too, especially since they’re rewriting pieces of the browser engine at the same time.