Re: You tell me,
Irrelevant. Once promised, it wasn't their call to make anymore.
Not in the slightest bit irrelevant. If the developer feels that adding a promised feature would ultimately have a net negative impact on their product/project then it's absolutely their call to make. It may have been poorly communicated, but that's what it seems like here.
If you're a KS backer then maybe - just maybe - you have a right to be upset about that one thing. But if that's all you were looking for in the game you should've saved your money and bought it retail when you knew the launch day feature set.
You go into KS projects because you hope to see them come to fruition, but that doesn't give you any sort of right to your money back if the scope of the project is changed. Hell, you should expect to never see your money again. And if the project delivers (and Elite Dangerous has delivered in spades) then that's great. You got something for your investment.
However, Kickstarters are not risk-free enterprises. And the sooner this sinks in, then the better of KS projects will be.