It's not a net neutral for most companies. It's a huge benefit for all the companies in that area. Skilled professionals have a choice of region and company to work in. IF they choose one with better terms for them, then that region will have a more skilled pool of workers. This benefits companies in that region. One could argue that the stronger ecosystem and pool of employees creates significant benefits that outweigh any corporate advantage due to restricting employee mobility. That's what the above reference is arguing.