I think there are a couple things that are fueling the rise in D&D. One is that there is no longer a social stygma to playing D&D, or Larping or any other RP type game. This younger generation is more likely to not care what you do in your free time. I’ve actually stopped going to the Seattle Comic Con because it is to crowded, it’s a crazy world.
Second is that 5E is extremely easy to pick up the basics and you can have someone DM almost right out of the box.
Third the explosion of the internent has pushed the game in two way, one if you don’t have friends available near you, you can get a group of gamers from across the country to play online. If however you have friends nearby, it’s an activity that can draw you together in one room, that puts social media/ ultraconnectivenss aside for a few hours.