Was the black death a tipping point towards modern society?
Without an initial labor shortage, there is no incentive to mechanize and automate (and muscle-power can only go so far up the technological tree).
Magical healing could prevent the pandemics that triggered the earliest industrial revolutions. (and without a railroad, there is no large scale coal mining or iron production ... and, therefore, no industrial age to free farmers and craftsmen up for more advanced technologies.)
Would you be prepared to say that without the black plague technological advancement would have been impossible? I mean, that labour shortage favoured advancement is entirely plausible even if perhaps not so certain. But than in absence of said shortage technological progress would be impossible, or even just very unlikely, seems an entirely different and more contentious proposition.
In my specific case, magic is not so powerful or widespread as to avoid the effects of plagues and the like, therefore it would not work anyway.
A civilization that remembers its past, yet not its inventions(or even the details of the inventions), and that suffers from frequent, catastrophic ice ages would probably suffice here. The ice ages would have to be long enough to keep the people mostly holed up in certain pockets, so that there is still a continuation of language, however the memories of previous civilizations are passed down and eventually told as mythology. The ice age would lift with new soil deposits covering the old civilizations' works, and those remnants mostly destroyed and eroded. Somewhat like Atlantis, but with a much broader sweep and a good explanation for magical beliefs or whatever you want to do.