That is just not correct. As someone who has done the budgets for PhD hiring and funding, you are just wildly underestimating the overhead costs, benefits, cost of raising money, etc.
The "3-5" is certainly overstated, but you definitely can hire ONE PhD for that price, just as you can hire a SWE for $120K or a knowledge worker for $24K. The point is that from a CEO's perspective "replacing all the humans with AI" looks a lot less compelling when the AI costs the same as a human worker or even a significant fraction of a human worker.
Being able to control their every move, scale them to whatever capacity is required, avoid payroll taxes, health plans and surprise co-pay costs, equity sharing, etc might make this worthwhile for many companies.
That said, the trade-off is that you're basically hiring consultants since they really work for OpenAI :)
The benefit to an emoloyee is that you don't have to control their every move. They can do work while you aren't even thinking about the problem they are solving.
Again, irrelevant. We're talking about orders of magnitude here. Current pricing is in line with most SaaS pricing - tens of dollars to hundreds of dollars per seat per month. Now they're suddenly talking about thousands of dollars to tens of thousands of dollars per seat per month.