It was mass-collusion between big companies to prevent people from exercising labour mobility. Poaching is illegal, i.e. theft from an individual or the crown; we shouldn't encourage treating people like company property.

yes, which is why Apple got massively fined for doing it -- nowhere near enough to compensate all the depressed engineering salaries though.

Yes and they got in huge trouble for it. It was a massive scandal. The only reason Apple wasn’t made an example of was because all the other big companies followed suit and did the same thing. It was Steve Jobs that drove this monopolistic behavior that could have turned out much worse for Apple.