Bethesda is a capable developer, not the best beta testers, but capable. To think they didn't take the chance to learn a few things on how to make a better Fallout game from the creators is ignorant and foolhardy.
I look forward to more Fallout on the East Coast, Obsidian can have the West, Bethesda can develop the east where they can make their own bit of Fallout lore. Maybe Obsidian can focus more on rural combat and exploring a desert, while Bethesda can create more urban ruins to explore.
All in all, to believe New Vegas is going to be better than what is presumed to be Fallout 4 because the developers first title in the series didn't sit well with a vocal minority who believe they are beyond redemption is beyond [censored] stupid.