And has all sorts of other negative social side effects, and lacks the general improvement to quality of life of Dannering.You are correct, however the changes gained by Dannering the newborn while huge are minuscule compared to Garricking everyone. Which can be applied to people who aren't newborn and speed up the whole society by orders of magnitude
In a Garricked society, no one can ever slow down, or they'll be left behind since once they speed up again everyone they know will be dead of old age; their entire culture as well may have been dead for subjective centuries. And if everyone is always in fast mode, there's a strong "if everyone is super, no one is super" effect. Plus the outside world is at a standstill.