John Larkin has his preferred delusions. Getting a Ph.D. in Physical Chemistry isn't what most people would described as a failure in chemistry. Since he doesn't know the symbol most elecronic engineers use for frequency, his ignorance about what ex-chemists might do isn't exactly surprising. He could seem enough examples my habits here, but he long ago worked that I don't post the flattery he craves, so he doesn't bother to look at them.
Don't encourage him. It's not even his slur, but one he poached from James Arthur, who should have had enough sense not to confuse the occasional typo with actual ignorance. Not that James Arthur had much sense - he confessed to being a paid shill for the Koch brothers here (back when there were still two of them) and has gone quiet ever since.