Hmmm I see the side of your argument....And I can see how that might play out for some companies.
But let me offer a counterargument. When you have something perceived as valuable to offer people generally do not look or manufacture reasons to exclude you from hiring.
And if you work for a company and you deliver exemplary work they will (or at least SHOULD) also make efforts to keep you there
Companies should know that they increasingly have to fight to keep their talent and they sure as hell have no problems brazenly poaching talent.
The idea that hiring somebody who has a fantastic skillset but might leave is a risk or waste of money is shaky logic....(I do acknowledge that shaky logic exists in the world though)
I err on the side of going after great opportunities rather than a track record of loyalty...
The thing is if you are prudent about the opportunities you are chasing you likely would have spent enough time at one of these places to deliver something tangible....
Basically this, couldn't have said it better, especially the bolded