Is this an actual statistic? I certainly think that reading is a decreasingly popular activity, but I would be interested in seeing where you get this twenty years time frame specifically.

I'm not sure this series really converts people towards novel reading, but rather converts novel reading to a more serialized format. It can make a story more approachable, in my opinion, the same way a movie is less approachable than a series when both are of equivalent lengths. Breaking things up into digestible chunks can allow you to go into greater depth in the long term, which is also why I believe many novels evolve into a series of novels.