A song about being on the Autistic spectrum. People with autism or Asperger's Syndrome refer to non-spectrum folk as "Neurotypical".
People with autism are often charactarised by highly ritualised, even compulsive, behaviour, social awkwardness and very specific obsessions: modes of transport ("...I like cars and planes and trains...") frequently feature.
The song is sung from the perspective with someone with autism, observing the neurotypical world.
One of my very close relatives is on the Autistism spectrum. On May 4 2020, he did indeed dress up as Darth Vader and did his weekly shop in Sainsbury's supermarket in full regalia and -- whilst observing social distancing measures (the COVID-19 pandemic was still raging) -- managed to entertain all the shoppers thusly. I kind of admire his unselfconscious "gung-ho" ness!