It is hard for us to judge what is a reasonable price for this camera. We do not know the research and development costs, how those costs will be amortized over time and units, etc.
Also, this is a true "professional" camera which means that the purchases are expensed against a corporate budget and represent a capital investment that will be accounted against taxes and will be amortized over time in the company budget. This is true whether the purchase is by a good sized company or by an individual professional photographer. What is sensible is what works economically in terms of the expense versus the return. That is the analysis that every professional has to make. My guess is that it will be sensible for most professional who are committed to the Nikon system. It will similarly, not be sensible for amateurs like me.