Good what olds like me have WOW or Everquest or Allods Online and there still expansions for those games and will be for many years, so we can play those games.
I find this really hard to predict. Is it just a phase i.e. are we going to look back on this time like an opium epidemic? Or is ultra short form "content" the new norm?
So many people are overworked, underpaid, and overstimulated to distract from the former two. Many parents fall victim to this and just want their kids to be quiet and distracted, and so they give them access to smartphones and tablets; chock full of high stimulation shlock, carefully crafted by multibillion dollar vampires to be as addictive as possible. And the degeneration self perpetuates. Ad infinitum though?
Similarly, I have VERY young nephews of 4 and 7 years old -turned 7 days ago-, and for example another thing that surprises me is that they are more fans of Sonic (they have some Sonic 50 to 100 pieces puzzles at home) than Mario.