I'm disputing your claim, it's only fair that you produce the data, however it takes such little time to Google "apple open source contributions":
https://open source.apple.com/projects/
I wouldn't call their contributions here insignificant. I'm not sure comparing them to Google or Microsoft is productive given how vertically integrated Apple is. What about Samsung? Sony?
It just seems uncharitable to imply they give back so little it's newsworthy when they do. It seems to me that they give back a fair bit, and that doesn't seem newsworthy to me, and I don't really understand why this is on the front page.