Your “rare” cruiser is from the 1941 edition.
There are no cruisers in the 1941 game. YG is referring to the early version of the Hipper-class cruiser sculpt, which had a transom stern (meaning a square back part). It first appeared in Anniversary, and I think it was also used in Europe 1940.1. The later version of the German cruiser sculpt has a cruiser stern (meaning a pointy back part). My theory is that the sculpt was redesigned to avoid confusion with destroyers, since most A&A destroyers have transom sterns.
Yes, the German cruiser I’m referring to has a square back stern, however, I personally never got them confused with destroyers because of their bow shaped width. The only reason why I would question your theory about why they changed those German cruisers, is because the later ANZAC cruiser vs destroyer sculpts causes the same confusion they maybe tried to avoid earlier.