It's the 1990s because DR V60 was the 106 these days a DB BR345 346 1.520 m tracks 347 Orange and Beige Stadtseexpress coach DB BR232 in the DR BR132 paint job. The closest I came in making DR V60 it's using its West German equivalent DB BR363 in the Orange paint job for DR V60.
Pragmatic decision From Wiki: Die Verantwortlichen in der DDR waren sich nicht sicher, ob sie in West-Berlin die Betriebsrechte behalten würden, wenn sich der Name der Deutschen Reichsbahn änderte, weil die Westalliierten nur ihr die Betriebsrechte gewährt hatten. Es bestand die Befürchtung, dass einer DDR-Staatsbahn, wie auch immer sie firmiert hätte, die Rechte hätten verweigert werden können. Für die DDR war es auch propagandistisch wichtig, die DR-Strecken in West-Berlin als eigenes Territorium zu deklarieren. Dies führte bis zur Wiedervereinigung 1990 immer wieder zu Streitigkeiten zwischen östlichen, westlichen und alliierten Behörden wegen unterschiedlicher Rechtsauffassungen. Auch spielten Vermögenswerte der DR im Ausland im Streit zwischen DB und DR hinsichtlich der Beibehaltung des Namens eine Rolle. Dies betraf besonders die Schlafwagen- und Speisewagengesellschaft MITROPA. English: Those responsible in the GDR were not sure whether they would retain the operating rights in West Berlin if the name of the Deutsche Reichsbahn changed, because the Western Allies had only granted them the operating rights. There was a fear that a GDR state railway, whatever its name, could have been denied the rights. For the GDR it was also important in terms of propaganda to declare the DR routes in West Berlin as their own territory. Until reunification in 1990, this repeatedly led to disputes between eastern, western and allied authorities due to different legal opinions. DR assets abroad also played a role in the dispute between DB and DR regarding the retention of the name. This particularly affected the sleeping car and dining car company MITROPA.
West Germany part of MITROPA became DSG for Deutsche Bundesbahn which is what you would have seen attached to a SNCB NMBS Sleeper train to Hamburg at Aachen Hbf 1966 or MITROPA DR DDR Sleeper Coach on Schnellfahrstrecke Köln-Aachen 1966
Keep in mind that the word "Reich" (= roughly, realm) doesn't by itself have any particularly nasty connotations: Frankreich France, Österreich Austria, Gottesreich Kingdom of God, Heilige Römisches Reich Holy Roman Empire. A kingdom is a Königsreich; DTG is located in the Vereinigtes Königsreich Großbritannien.* The Weimar Republic 1919-33 was called "Deutsches Reich," its currency the Reichsmark and its national railway Deutsche Reichsbahn. So the DDR's railway had a pre-National Socialist name that had nothing to do with the infamous Drittes Reich. *und Nordirland
I'm aware of the word's meaning, yes, but the other half of Germany tended to move towards Bundes in the mid 20th century, for some reason!
As already mentioned, there were legal/practical considerations for keeping the name. What good reason should there have been for changing it afterwards? Just adds more unnecessary costs at that point.
I don´t think it was much of "pragmatism" rather than greed. The "Deutsche Reichsbahn" held all the rights to its real-states and revenues in West-Berlin. The S-Bahn in West-Berlin - managed from East-Germany(!)- generated much needed convertible currency as train tickets were paid in D-Mark and the commies didn´t want to lose that. Willy Brandt, mayor of West-Berlin in the 1960s, even called for a boycott after 1961: "It can´t be that the communist government finances the Berlin-Wall with the incomes from the S-Bahn." Sure enough, a maiority of the (West)Berliners followed and revenue dropped significantly. In the 1980s finally the S-Bahn in West-Berlin was a wreckage and a loss business. Just one of the many political aberrations in a divided Germany. I remember very well that we kids DID ask ourselves why on earth this somewhat outdated name from a bygone era was kept alive. Of course, the answers would only come after 1989, as everything was a state secret in the GDR.