Indeed, I'm very concerned about this. Though i think it's a case of tragedy of the commons. Every company individually optimizes for themselves, fucking us over in the aggregate. But I think any executive arguing for this would have to be a pretty big company with an internal pipeline and promoting within to justify it, especially since everyone else will just poach your cultivated talent, and employees aren't loyal anymore (nor should they be, but that's a different discussion).
But, then again, how companies going to get senior employees if the world stops producing juniors?