Ooh as the granddaughter of very loving but OMG strict (East) Prussian grandparents, deMichael I would be wary of lauding "Prussian virtues " in the same way that people speak glibly of Victorian values, forgetting all the hypocrisy, misery, exploitation, intransigence, grinding poverty of the seamy underbelly of the Victorian era.
I also absolutely disagree from my own perspective of visits to Germany to my GPs who had relocated to near Osnabrück through to 1968 that these "Prussian" values were typical of Germany through the to the 70's. Of that generation perhaps, but not my own teenage and young adult contemporaries
Earlier up thread you said Prussia still exists because we still have Berlin and Potsdam etc. I found Potsdam very beautiful when I visited on several occasions and see Berlin a vibrant, cosmopolitan, "happening" trendy city now the very antithesis of the city as conceived in its Prussian heyday.
The thing I find about modern Germany is how unGerman things seem nowadays. Yes the trains still run on time and litter is absolutely frowned on, but the stiff, formal society of my childhood is no more. Germany has become a truly modern European country and while my experience does not include the most recent events since 2014, it seems to me a country which neither my mother or my grandparents would recognise today.