Notes:

This is an actual argument that astonishingly comes up every. Single. Time. Opponents of civilian gun ownership unironically argue that Hitler didn't disarm people, but was instead very much pro-gun. At best this is a very one-sided depiction of events, at worst it is outright Holocaust Denial. Not one credible Historian denies that there had been increasingly repressive laws against Jews over the years, which naturally included confiscating their guns and knives:

"Immediately following the „Machtergreifung“ in 1933, the weapon laws of the Weimar Republic were used to disarm Jews, or to use the excuse of "searching for weapons" as a justification for raids and searches of homes. Because the weapons law of 1928 gave the police the authority to issue or withdraw weapon permits, Jewish weapon owners were disarmed through warrants issued by the police. For instance, the president of the police of Breslau enacted an order on 21 April 1933 which stated that Jews had to give their weapons and shooting permits to the police immediately. After the Jewish population was judged as not to be trusted, no weapon permits were issued to them. The weapons law was also used for searches of homes and raids. The preface for that was the allegation that the victims of these searches stored large amounts of weapons and ammunition. A prominent example is Albert Einstein, whose summer residence in Caputh, near the Schwielowsee was searched in spring 1933. The only item found there was a bread knife." – https://en.wikipedia.org/wiki/Disarmament_of_the_German_Jews

Stefan Molyneux once summed up neatly why Hitler strengthening his police, military and paramilitary forces is not surprising in the least and certainly not in contradiction to Gun Prohibition:
“If you are for gun control, then you are not against guns, because the guns will be needed to disarm people. So it’s not that you are anti-gun. You’ll need the police’s guns to take away other people’s guns. So you’re very pro-gun; you just believe that only the Government (which is, of course, so reliable, honest, moral and virtuous…) should be allowed to have guns. There is no such thing as gun control. There is only centralizing gun ownership in the hands of a small political elite and their minions.”