Progressive stratification does not imply companies will disappear. We might well end in a situation where people &quot;graduate&quot; from one social network to the next as they get older. So preteens will start on Snapchat, move to Instagram when going to high school, then Twitter and&#x2F;or dating networks in college, LinkedIn as they hit the job market, and eventually Facebook when settling down.<p>Most of our cultural output (books, films etc) works like that already.