The MS employees I've met/interviewed were literally not allowed to read open source code or sample code on Q&A websites. Of course that was mostly 5+ years ago and I don't exactly ask them if their policies have changed.

When at Microsoft I was expected to be on top of Stack Overflow for our product, and there's a whole program where if you contribute to open source you get to vote on where the monthly OSS sponsorship goes.

I've linked to WebKit source before in exec reviews and no one bats an eye. So, changed, I'd say.

Im on StackOverflow all the time and we use OSS code all over the place. Either they were pulling your leg or you badly misunderstood something they said.

I did not. Talk to some MacBU people.

It is in California at least - you can moonlight on whatever you want when you are not on company time or equipment.

Our vacation also doesn't expire and we also don't have non-compete clauses.

This is not how California law works, because you left out the (in this case very important) part where this is exclusive to things that don’t compete with your employer. If you work at a FAANG, the number of things they work on is very large and consequently they will claim large control over what you do.

Which means it will eventually be the law.