The fact that a lot of the Einsatzgruppen commanders had PhDs is representative of a larger pattern within the SS leadership or more specifically the Reich Security Main Office (RSHA) leadership.

The RSHA was one of several – and next to the Economic and Adminsitrative Main Office (WVHA), which was responsible for the administration of the Concentration camps – arguably most important SS main office, meaning the central adminsitrative structure of the SS and its state within a state. The RSHA was designed to be largely responsible for security matters. That included, among other things, being the highest adminsitration for both the Security Police, which included the political police Gestapo and the SD, which served as the SS' intelligence service, and the Ordnungspolizei, which amounted to both the criminal police and regular police.

The RSHA was laregly run by a group of men that were surprsingly homogenous. This has been laid out in a book I would highly recommend to anyone interested in the subject matter of the SS: Michael Wildt's An Uncompromising Generation: The Nazi Leadership of the Reich Security Main Office, University of Wisconsin Press 2010.

Wildt effectively writes a collective biography of the leadership of the Reich Security Main Office and arrives at several pattersn that characterized this group: First of all, most of them were born after 1900, which had the crucial effect that hardly any of them took an active part in World War I. Crucially though, they lived through the propaganda and cultural atmosphere of the war and soaked it up wihtout having the demystifying experience of actually fighting in the war. This is where Wildt's title stems from: According to him, both the experience of the war and, crucially, its revolutionary aftermath when the revolution in Germany changed everything they knew often in a violent matter, made them into people who were ideologically uncompromising. Meaning that they viewed the world and politics in a very manichean way: A struggle between what is good and what is evil to the death and without any sort of chance to tamper or compromise.

Many of them put this first into practice when they joined the Free Corps, meaning paramilitary corps often made up of veterns of the war but also comprised of university students who fought both in border conflicts in Poland and the Baltics agianst non-German, often Soviet supported troops and – more crucially – against left-wing revolutionaries in Germany. Free Corps murdered Rosa Luxemburg and Karl Liebknecht and enacted a bloos bath to end the Munich Soviet Republic. This was the first step in a crucial development for the later formation of the SS and the RSHA: In the Free Corps networks between these men and a whole variety of already important or later to be become important people of the völkisch scene in Germany were created. Somethign these men would tell and something that Wildt points out, hardly a thing tends to form as strong a bond between extreme right-wingers like murdering together. It's estimated that these Free Corps killed at least 3000 people between 1919/19 and 1922, from liberal politican Walter Rathenau to seveal women in Munich who refused to conform to standards of conservative feminity.

After the Freecorps time ended and when it became relatively clear that the Republic would stand, at least for some years, these men, most of whom had come from academic middle class households who had done well during the Empire, went on to university and continued to form their völkisch right-wing networks in organizations such as Burschenschaften (traditional student associations formed in the 19th around resisting Napoleon and creating a unified Germany; they dress silly, fence and are a bedrock of völkisch politics until this very day) and university association.

Two-thirds of the later leadership of the RSHA would study at university, partly thanks to Weimar's opening of the universities and their policy of social mobility. Of those who went to university, the vast majority studied either law or Staatswissenschaften, which is losely translated as "state science" or "state studies" and which in a time before political science was really a thing, is a combination of law, sociology, economics and political science designed and intended to educate people who woiuld go on to become state bureacrats and administrators. It's a more expansively designed law school but not with the intention of becoming a full blooded lawyer or judge. The second largest group studied something in the humanities, mostly either Germanistik (German language and literature) or history. And only small part came from a STEM field. Of those two-thirds who studied, half got a doctorate in part because that was pretty much the end goal and also an automatism for those who studied law, partly because it was something that came in handy during the economoic crisis of the twilight years of Weimar, and in part because it fitted their ethos of highly educated, highly capeable ideological warriors of the new order.

A crucial part of the university experience for these men was that they formed the ethos that would later come to define the RSHA: The fighiting administration (kämpfende Verwaltung). The idea here was that the new völkisch, nationalsocialist ideolgoue warrior adminsitrator would be able to combine a wide range of activities: Like a Renaissance man of ideological violence, the ideal Nazi leader would not only be able to run a state or adminsitrative office in practical terms but they would also take an active part in the ideological fight. In practice that meant that while most of these men ran various offices and subdivisions in the RSHA and its predecessor (the RSHA was formed in 1939), it was also expected of them to collect "practical" experience of the fight. This meant that a variety of them did run a Gestapo offices somewhere in Germany or were involved in running and administering the concentration camps and that they took part in the war in Soviet Union.

The conflict with the USSR was to be the peaking achievement of Nationalsocialism and for the men of the RSHA it was the final and ultimate conflict with Judeo-Bolshevism they had trained and waited for. Therefore it was expected of them and they also expected to take an active part in that war. And so they took over the Einsatzgruppen and rotated in and out of those, effectively taking a break from their office and administrative duties to spend time in the East killings Jews.

So in short, a bunch of higly educated academics ran the Einsatzgruppen because they were a group of people who perceived themselves as elite, ideological warriros who would split their time between adminsitering and actively taking part in the fight against the enemies of the Nazi order they wanted to erect. Coming from a surprisnigly homogenous group they all had a similar set of expereinces that formed what they would become.