It probably depends on the individual in question, of course; but I don't see the prevalence of gadgets as a sign that people care more about gadgets than people. I love my gadgets as much as the next person. My grown kids and siblings have all the same gadgets that most other people do too. Still, it's pretty clear that we're the same, close, group of people that we've always been (and that a whole lot of people wish they could be with family members/friends). In fact, to the person who DOES value the people and relationships in his/her life, a lot of gadgets just make it even easier to stay close.
So I think that being materialistic is either in the eye of the beholder, or else it's in the heart/mind of SOME owners of gadgets (but it that's the case then it would be there whether or not the person has gadgets).
I think of when my kids were little (before gadgets were what they are today), and their father and I would be at the dining room table, each of us reading our own books/magazines. All three kids would be nearby in a chair or on the rug, reading their own books of one kind of another. We'd occasionally "check in" with each other, but were generally absorbed in enjoying our reading. There was something very warm and cozy feeling about all of us knowing we were together, and enjoying doing the same thing at the same time; even if it meant paying attention to our own reading. That wasn't "book materialism". :) It was "a shared family activity". I'm not sure that everyone having his own gadget at the family dinner table is a whole lot different than that. In the right family and circumstances it's almost just another way to have "some other little thing" in common with everyone else (like the books/magazines we had were when we'd all be sitting around and doing the same thing).
I think people basically bring whoever/whatever they are to any situation. If there's something "empty" going on among a bunch of people, I think it's more the people than it is something like either gadgets or books. :/