I would love to deliver a TED talk on the costs and issues with developing new airframes vs adapting existing ones to new roles.
However I'll leave you with an analogy. If you were in the business of delivering mattresses, would you rather have a GMC cube van that is perhaps not aerodynamically optimal and has a weight capacity that exceeds your requirements but has parts available around the world and every mechanic and driver has seen before. Or would you rather develop a custom mattress delivery vehicle that no one knows what to do with, doesn't fit in normal parking lots and can only be maintained and driven by your own specially trained team of mattress delivery vehicle specialists. How many mattresses do you have to deliver in a year before that option makes sense? What happens when GMC sees this giant mattress delivery market and pulls the box off one of their larger pickups and attaches a mattress carrying unit?
However I'll leave you with an analogy. If you were in the business of delivering mattresses, would you rather have a GMC cube van that is perhaps not aerodynamically optimal and has a weight capacity that exceeds your requirements but has parts available around the world and every mechanic and driver has seen before. Or would you rather develop a custom mattress delivery vehicle that no one knows what to do with, doesn't fit in normal parking lots and can only be maintained and driven by your own specially trained team of mattress delivery vehicle specialists. How many mattresses do you have to deliver in a year before that option makes sense? What happens when GMC sees this giant mattress delivery market and pulls the box off one of their larger pickups and attaches a mattress carrying unit?