The reason two year old kids can use an iPad and aren't ready for standard Legos is because the latter requires more skill. TFA claims claims that exposing kids to technology is causing our civilization to spiral down the drain, but provides no evidence whatsoever, other than anecdotes and conjecture.
While no hyperbole such as civilization spiraling down the drain or even anything close to it TFA say that:
Children are arriving at nursery school able to "swipe a screen" but lacking the manipulative skills to play with building blocks, teachers have warned. They fear that children are being given tablets to use "as a replacement for contact time with the parent" and say such habits are hindering progress at school.
While as you write there is little support for what is written beyond anecdotes and conjecture it most definitely is something that deserve attention and scientific studies not people getting their panties in a bundle over imaginary luddites.