I suspect there is a communication barrier between high-IQ and average-IQ people. Also, people tend to connect with each other through shared interests, and many with high-IQ also have high openness, lending oneself to have unconventional interests. With fewer people like you, it can lead to literal social isolation, and a feeling of disconnectedness with others. I don't think this is autism per se, but I can see why many people with high IQs may think they have autism.