First of all, with the caveat that, as is so common with psych studies, this was performed on undergraduates only . There is no reason to assume that this would necessarily extend to a 30-year-old mother, a 40-year business executive, etc. (To the contrary, one could also imagine that having their phone on them increased their capacity to think about other things, with the peace of mind that they can get things done…
What goals? So far those goals seem to be related to planet destruction via excessive consumption. Slowing down is what can save us from extinction.
Conversely, if you're optimistic, then you might imagine that all the people trying to save the planet are using the coordination and information that cellphones enable to gain more influence and achieve that.
Five hundred years ago, I'm sure people made the same arguments about books -- that they kept our concentration from the immediate present, and could be used to achieve bad things. I'm pretty sure books turned out to be a net positive. I feel the same way about cell phones.