no I don’t think so, a gammon (at least to my understanding) is more generally prejudiced about most things- climate change, sexual orientation, the indisputable greatness of Britain, obsessed with the war even though none of them lifted a finger, dislike of immigrants and distrust of foreigners, often daily mail/ express readers, pro brexit, generally 50 plus- look at CVDs avatar and you’ll see plenty of ‘em
you wouldn’t immediately call someone a gammon if they were a racist, you’d call them a racist- a gammon wants to go back to the good old days of the Empire and hates anything which even mildly disputes their way of viewing the world, which is based on how things used to be & incredibly insular.
I don’t use the word any more as obviously it was offending a few people