Well we assume that Klingons have always been "all" about the warrior code. If you consider Medieval Europe and Feudal Japan embarrassed strict codes late in the period one might consider that now that the Klingons are well established they are more embracing of their traditions. They seemed much more pragmatic in the 23 century. Upon entering into a space building empire mode they may have strongly embraced a scientist class and even warriors were well educated preferring technology instead of focusing on hand to hand combat but with peace with the Federation you see a cultural shift to "get back" to their roots.
This may have even been in waves, there is a concept even in the US of the cultural pendulum wherein we embrace liberal and conservative views.