Having a 10x engineer(or even worse, a 500x engineer in this alleged case) is a huge risk for the company, should the engineer want to leave or if they are incapacitated in a tragic event, the company is severely handicapped, ideally a so-called 500x engineer should spend less time writing the actual code and instead mentoring/managing others to scale up their knowledge, should the company do this right, they might not deliver on time, but they'll have a much wider array of experts when something breaks or for the next projects, reduces overall company risk and it's more profitable in the long run.