It could just be that the Dotharl can be both vicious and bloodthirsty enough to massacre other tribes as well as reasonable in their dealings with them, depending on the specific time or situation. Mass murderers don't need to be axe-crazy all the time, after all.

Anyways, I greatly enjoyed the lore of the Steppes (even if certain non-Xaela characters introduced in that segment fell a bit flat for me) and my time spent there, and while Yanxia is probably my favorite zone so far, the Steppes is the only one I'm itching to go back and complete all the various side quests in. Lots of little details tucked away, and heaps more lore integrated into the experience than expected. I had my Encyclopedia open to the page with the 51 tribes next to me the whole time, looking one up each time it was mentioned. It's always nice to see lore expressed organically in the game itself.