From a reader:
“Shyster” is apparently as anti-Semitic as “niggardly” is anti-black. Its apparent etymology (as I’m sure you found) traces back to a German word for defecation. But it’s not news that shyster was meant to be used derogatorily about lawyers in general.
This really boils down to an IQ problem on the part of the Observer, which you might have emphasized more, coupled with the ill-will and refusal to engage in a substantive discussion about ideas that you pointed out.