“the word ‘svengali’ has come to a refer to a person who, with evil intent, dominates, manipulates and controls a creative person such as a singer or actor.”
I’ve heard that word all my life and this is the only way it’s been used. I never noticed any connection to Jews; in fact I didn’t even know until today that the original Svengali character happened to be Jewish. I really don’t think that’s a significant part of the word’s meaning, at least not for a long time.