Imposing gun control was ALWAYS one of the first steps.
In academic circles, the historical phenomenon is referred to as democide. The actual 20th century totals I've seen seem to average around 130-150 million.
One of the first examples the video gives is the Armenian genocide. I'm unaware of any gun confiscations on the part of the Turks. In fact, the Armenians put up a spirited, armed defense at Van. As with other such episodes, institutionalized coercion and overwhelming force of numbers played a much larger role than the confiscation of firearms.
To hear some folks tell it, if German Jews had guns, the Holocaust would have never happened. This is specious at best. There were roughly 500,000 Jews in Germany (out of a population of 80 million) when Hitler came into power. Even if they had access to firearms, how many of those would be willing and trained to use them effectively?
A few thousand, perhaps. Not enough to band together for an organized, effective resistance. Certainly not enough to give the Schutzstaffel pause. They might have scored a few casualties, but one only has to look at Hitler's treatment of Poland (who did resist with force of arms) to see what little effect it would have had.
While it seems to be a corollary in many cases, implying that gun control is the cause
of oppression is a shaky argument at best.