I suppose the idea is that those junior developers who weren't hired will spend 10 years doing intensive, unpaid self-study so that they can knock on the door as experienced seniors by that time.
Are you serious? How on earth are these people going to eat or pay rent for 10 years? As well, most companies would laugh you out the door if you were applying a senior role without any experience working in the role.
I'm not laughing at all. I'm definitely not making fun of those who may be affected by this. My sarcasm was directed at people or companies planning to implement such ideas.