If you only ever judge WW2 by what Hollywood shows us then your as ignorant as can be. The Russians play an enormous part and this series shows just how it was for them. Men & women fighting together in difficult conditions. Political Commisars in every unit indoctrinating the troops and all fighting a dirty war that is seldom fully recorded here in the west. D-Day saw 7 divisions land on Normandy. Russia fought 50 divisions of German infantry and armour at least.
As for the production, it is representational and captures the feel very well. Russians don't have the luxury of big fancy CGI firms doing their fight scenes and to be honest it's the story line that makes the show, so we'll done to the script writers and the actors.
I think a lot of Russian made programmes and films are greatly underestimated. If as a country, they weren't so keen on poisoning people or cyber attacking someone then they could be a big player in the Movie business.