i think he allowed himself to do it as part of his edgelord persona, trying to trigger people on purpose. the motion is intentional as his arm shoots straight out to the side as opposed to being directed to the center of the crowd or sweeping across the crowd as if to spread his “heart” as it were.
the autism defense is one that i think is being used to try to checkmate the left on the subject, as they are the most offended by the gesture but also more likely to be sensitive to neurodivergent persons and potentially less likely to criticize their actions.
in short, i believe he intended the gesture as interpreted, just not as a genuine expression of his personal beliefs. that being said, i think hes a white supremacist fascist, but i dont think he thinks hes a white supremacist fascist.
the scariest implication of this whole business is the most favorable interpretation of the nonplussed reaction of the majority is that they are in such denial that a nazi government could be possible again in a first world country that they cant see it for what it is. that is to say, the exact things the people who lived through it had been vigilant to remind us about ever since.
i definitely agree that it empowers legitimate nazis, which i suppose could be his way of cultivating a voter base which no other candidate would openly support but would vote for whoever he throws his money behind as trump will no longer be a valid candidate. a best case scenario here would be that this kind of attention is too much even for trump to tolerate and will cut ties with him. i feel that would be likely to happen regardless, as they are two narcissists of the highest order, but it would be better if it happens sooner.