I have friends that work for Apple, Google, Oracle, whatever. And I have friends that have quit en-masse from those companies. They almost always quit because they went from a cool startup to a tiny cog in a gigantic machine. These gigantic internet companies consume smaller companies and spit out all the parts they don't like. In many cases, that's most parts.
This is not an Apple problem, it's an industry and maybe even a societal problem. I don't even think it's possible to get a good job, get an A+ rating for every performance review ever, and expect to stay at that job for 5+ years. After 10 years, you are too expensive to keep around.
It's a race to the bottom. Throw enough cheap shit at the wall and you'll eventually meet your short term profit goals but, damn, that's a lot of shit to clean off the walls. In fact, you may not be able to clean it all off.
Greetings, Humans. The machine churns. I'd like to introduce you to the grinding wheel...