To a rank outsider, the graphic looks like the sort of rubbish produced by magazines who want sales, SALES, MORE HITS, MORE READERS!!! and don't really care whether what they are pedalling actually reflects truth in a vaguely professional way.
For example, e-mail traffic is shown in decline, but I'm pretty sure more e-mails are sent today than in 1990. It's absolutely obvious that e-mails would be a smaller proportion of total traffic as, frankly, I can't type fast enough to compete with videos.
Percentages over time are completely meaningless when the total over the same time has changed as dramatically as electronic communication has in the last 20 years.
Incidentally, no doubt it will all change again. I don't like to ask too many questions about how electronic gadgetry can be so very cheap in the shops (near-slavery conditions where it's made?) or what happens to it when I throw it away. And perhaps one day someone will ask the question "Do I really want to know if 'Simon just did a big burp!!'?", and tweeting will collapse in a puff of triviality. There has to be something more meaningful in life.