While I don't argue that most folks (myself included) would be better off with more exercise, I find some of that graphic presentation to raise my critical thinking eyebrows.
Their "calorie burning drops to 1 calorie per minute" is the victim of well-placed rounding error. My understanding is that a human at rest burns about 1.4 calories per minute. By normal rounding rules, you can round that down to 1, and not technically be lying, but you throw out about a third of human energy use in the process. That's misleading. You should only round off when what you drop is not a significant fraction of the total.
Between 1980 and 2000 exercise rates stayed the same, and sitting increased by 8%. First, I'd like to see how they are defining their "exercise rates" and sitting time such that this is even possible.
After that, I'd like them to include some information on dietary changes between 1980 and 2000 before I'll even consider them accepting their suggestion that sitting is the culprit. If caloric intake increased in that span, then sitting probably isn't the real evil, now is it?
And heck, it's done all in black and red and white. No, they're not trying to manipulate your feelings at all there
Yes, they do provide some links at the end, but the initial presentation should not require them to be accurate and unambiguous about their conclusions.
Right message: maintain a proper amount of exercise in your life. But the method used to convey that message at first glance looks misleading - the ends do not justify the means.