“Eric,” a limited series premiering Thursday on Netflix, stars Benedict Cumberbatch, wearing an American accent, as Vincent Anderson, a Jim Henson-brand puppeteer, if Henson had had severe mental health issues, a drinking and drugs problem and on top of that was just kind of an angry, egotistical jerk. Henson is mentioned in passing, so we are not supposed to confuse the two, Vincent’s beard notwithstanding. (Coincidentally, Disney+ is premiering Ron Howard’s documentary “Jim Henson: Idea Man” on Friday, which will make that distance clear.) The setting is 1980s New York City, in its graffiti …