They shouldn't have to specifically state something will be available at launch, that has always gone the other way around. When you purchase a game or expansion, you EXPECT what was advertised and paid for to be there. They didn't specifically state the strikes would be there at launch. Or the story missions. Or the crucible maps. You assume you'll get the content you purchase when it comes out unless otherwise stated.

Yeah you assume and except but those are not for sure things that is on you. Also I do believe they did say not all the weapons will be available at launch in gameinformer but I have to check that. But even if they did not state the point is that it is not false advertising because they never stated it will be there at launch. You will get them but just have to wait on them, you are getting what you paid for.

They never specifically stated all the strikes would be available day one. Or the missions, or the crucible maps. In an expansion, a collection of content, content is included upon release UNLESS otherwise stated. Not the other way around. There wasn't an asterisk on every other thing they showed saying "this content will be available at the launch of the taken King".