I also find it funny that this sort of illegal government activity actually caught someone selling weapon parts

All it said was that he was selling accelerometers, which could be used in a variety of things (i.e. autonomous vehicles, commercial aircraft, etc.):

The defendant was accused of unlawfully selling Q-Flex Accelerometers—models QA-2000-10, QA-2000-20, and QA-3000

There was no statement of intent (in the article at least), so saying these were to be used for weapons seems a bit premature.