Although viewing habits are evolving, I don't think this presages an evolution in humans - we still enjoy social experiences, watching movies and television shows together on the couch or in a theater, etc.
So I imagine this reflects a certain partitioning of the market. Going forward, young people will probably enjoy certain types of media on one kind of screen, other types on another. Which does indeed seem like it should slow development progress on the one that loses market share.
At least we got up to 1080p as a standard and will probably have viable OLED soon. 4K might be a plateau for a decade or more, though. As someone who has invested heavily in Blu-Ray for my viewing, I'm pretty OK with this.