There is video footage out there of Sean saying you could play with your friends, you could grief people, you could find someone else, it's just unlikely (which in gamer-speak, is just a potential challenge) and there's a 'floating' open lobby around every player.
NMS is a case study on the importance of good messaging and marketing. Not everyone follows every piece of news like a lot of gaffers, so it's important to get it right first time and not rely on corrections/clarifications.
No doubt there are a lot of people being very disingenuous in their claims of what they understood the game to be, but regardless, this is a problem of Hello Games/Sony's making.
That said, the game still looks pretty damn impressive, and I'm really hoping the PC version isn't completely broken.