I know what you mean. I've seen so much footage of things showed at conferences over the past few years that shows content that never made it to the original game, but is now turning up in DLC. I'm surprised no-one has brought a lawsuit against them for that, but again, we probably all -blam!-ed that up when we signed the Terms and Conditions. Lots of stuff gets cut from games in development, but whole planets? That seems excessive.
Still seems like false advertising to me but it bothers me that they can have that content at a show and then turn around and claim it was setup like that just for the show. It wasn't intended for the final product. The things they removed from destiny kind of make me wonder why they were there in the first place or if it was because they weren't prepared to put the game in production for ps4 and Xbox one. It's almost like they were an after thought. This is also why I kind of think the main story line got chopped apart and scrapped. Development for the next gen slowed everything down and they wouldn't have made their release dates had they kept trying to make a complete story. Making the grimiore was probably way faster to make than actually having to make cut scenes and a plot.