Edit: And perhaps I'm misconstruing your statement, which seems to have more to do with the decline in German culture after the purges rather than what led to the purges.
Quite a few people argued since then that the rise of fascism was surprising because of the intellectual environment, but that it was a actually a pre-requisite for it to happen that way. If that is accurate or not, is a different matter but one could make a point that the "German question" combined with the propensity for total, systemic philosophical systems in German culture contributed to the uniqueness of what happened during 1933-45.
That's not true. Hitler didn't liquidate the intelligentsia. The first programmable computer ( by konrad zuse ) was created during that time. The first rockets were developed during that time. Hitler didn't wipe out all the nobel prize winners in germany.
Germany was still a major intellectual center before, during and AFTER ww2.
Germany is still the 3rd largest producer of nobel prize winners with 106.
https://en.wikipedia.org/wiki/List_of_countries_by_Nobel_lau...
Germany didn't go anywhere. Hitler isn't germany. Hitler is just a blip in german history.
The reason Germany, England, and France (Spain didn't catch up because they had no reason to as a negative consequence of their enormous wealth at the time) excelled to such extent that this particular period appears like a very special and wonderful intellectual age, is that the rest of the world was for the most part severely under-developed. Germany didn't become less "wise".
Today the contrast is much smaller, but Germany continues to be a scientific powerhouse even if it isn't as evident.