Is there any measure by which the Germans today could be called a genetically superior race?
I am leaving the word 'superior' aside (it's ill-defined and strongly valuing).
In any way - unlikely. If any ethnic group is 'superior' (at least, intellectually) - then, ironically, Nazi main victims - Ashkenazi Jews. But while there is some genetic component, it is impossible to disentangle it from societal and historical factors. Here are some links, is you are interested.
When it comes to Germans, as far as I remember, they are not a group genetically distinct from, say Poles. Yet Slavs were considered by Nazi also an inferior race, to be enslaved or eradicated.
In any case, culture and socioeconomic factors seem to be much stronger than (relatively small). In particular, for Germany itself, there was a huge difference between West and East Germany, prior to the fall of Berlin Wall. It can be hardly explained by 'genetical superiority' of West Germans. An excerpt from Race, IQ, and Wealth by Ron Unz:

Consider, for example, the results from Germany obtained prior to its 1991 reunification. Lynn and Vanhanen present four separate IQ studies from the former West Germany, all quite sizable, which indicate mean IQs in the range 99–107, with the oldest 1970 sample providing the low end of that range. Meanwhile, a 1967 sample of East German children produced a score of just 90, while two later East German studies in 1978 and 1984 came in at 97–99, much closer to the West German numbers.
These results seem anomalous from the perspective of strong genetic determinism for IQ. To a very good approximation, East Germans and West Germans are genetically indistinguishable, and an IQ gap as wide as 17 points between the two groups seems inexplicable, while the recorded rise in East German scores of 7–9 points in just half a generation seems even more difficult to explain.

See also The East Asian Exception to Socio-Economic IQ Influences and The Myth of American Meritocracy (on how ethnicity can affect admission) by the same author.