Heh, what was said at all the times? "We are holding back content for surprises when the game gets released".
More likely there never was more content than what was shown in the BackerBuilds.
You think only Kickstarter games cut content and change shit? You think games paid by publishers always end up exactly the way they were planned?
Gollop is stupid not because he didn't deliver on what he promised but because he made any specific promises in the first place. Sure, if you're on Kickstarter, you have to offer people SOME kind of roadmap but you should always keep the specificity to a bare minimum because, as Daniel Vavra said, making a game is not a factory production, it's more like research and development and you're always mobbed by surprises and unforseen obstacles.
Now it's entirely possible they cut content in the vanilla with the intention of selling it as DLCs. But it's more likely they just ran out of time, money, talent or they did it while polishing and balancing the game. Or a hundred other possible reasons.