I think it's agreed that for content production, a laptop or desktop clearly wins.
For content consumption, which is what a bunch of people mostly use their devices for, a tablet is perfectly acceptable.
As one example where tablets shine as tools, not toys, is in aviation. Yes, I suppose a laptop could have been marshalled to store all the requisite charts and manuals an airliner needs, but it was the tablet and it's form factor that made the inroads. A tablet loaded with WingX7 Pro makes a perfect kneeboard in a plane, where laptops have always been awkward.
In any case, neither form factor should be dismissed out of hand. They both have their place.