Back to the original topic.
The only reason to build a 90deg v6 is if there is a complimentary v8. You take 2 holes out of the v8 and use the same pistons, rods, valves, bearings, etc. There is a large savings in engineering and development costs since much of the production machinery is the same or similar. If you were to design a v6 as a stand alone design it would be 60deg.