It's a low bar in the sense that a show can be misogynistic and yet pass the test.
But the show can also be a strong case for equality and fail it (ie. have both males and females involved in all conversations).
If a movie has only 2 characters, a man and a woman, and the movie is all about their relationship, then passing the Bechdel test will be a high bar for that movie.
The article mentions how many episodes in Voyager were very Janeway-centric, and yet didn't pass the test because in all the conversations there was one way or another one male involved, even though the focus was on Kathryn.
I feel that it's not a very good test in general. There are also shows/movies that don't pass the reverse Bechdel test (having 2 males talk about something not involving a female) and yet I wouldn't say those shows are sexist.