I find that my tablet has improved my head up/out time substantially. I get traffic, map, nav data and weather all in one place. A quick glance takes them all in. And the mount for the tablet is much closer to normal exterior sight lines. Compare this to having to look down, deep into the console at a couple of radios/nav's, flipping pages on the nav to check multiple things, or, horror of horrors, manipulating paper charts. Plus entering information into the tablet is so much easier and faster, none of this twist/press/twist/press nonsense.
However...it does tend to make one quite lazy about flight planning. No more tidy pieces of paper with freq's, runway headings, altitudes, etc. on them. Why bother when you can just look them up as you need them on the table with two or three taps? That was a joke, by the way
Best to do these things ahead of time, of course.
There's no doubt that the complexity of these tablet based tools can lead to excessive head down time when learning them. Therefore best not to learn them in the cockpit. I became quite handy with mine by making a point to use it whenever I was travelling as a passenger, whether that was in a car, commercial airliner (sit by the window for good GPS coverage) or in a helicopter when not flying.
However, however...I suspect the intent of the video was not to pick on tablets per se, but rather show a modern twist on the same sort of head down behavior fussing with a paper chart could cause just as easily.