I think a lot of the complaints (some very valid, some maybe not so much) stem from expectations that people had for the pack. From what I gathered from the response, the EP has things that people didn't expect (like the conservationist career or the rarely mentioned island ghosts/entities/whatever they are) and doesn't have things that people did expect (underwater gameplay, ability to vacation on the world).
It feels to me like the pack's direction (Living, so focused on the aesthetics of the world and some world-specific gameplay like suntanning and such) was not a good decision on the team's part with this particular pack. They clearly thought it was but the people who are disappointed with it also have a point (not always articulated nicely, but them's the internet rules these days, unfortunately).
That said, it's still beautiful, looks fun & while I don't have it yet, it's on my wishlist.