Bias or is it perhaps recognition?
This is all my opinions on the subject.
I think Jeanne Dielman is a bit too slow and artsy to really be considered number 1 without critics, HUMAN critics as there is no other, sticking a known female-directed movie they "appreciated" on the list because feminism in more "in" now than ever thanks to the MeToo movement. Now no one in their right mind would think MeToo is a bad thing, but no one in their right mind should ever consider that good things can't be abused. It's as common to defend something good and use it as an excuse for bad behavior as it is for a human to worry about what others think, so when you gather a mass amount of critics, there will be a few people worried about image.
I doubt, however, that any of them would've considered that Jeanne Dielman would make number 1, and that there were just mass amounts of people who upvoted them to say there were with the times, much like the mass amounts of RYM users who unwittingly secured three Beatles and eventually three Radiohead albums in the top ten albums. Hell, most I've ever given for a single director in my top ten was two: Coppola for the Godfather movies and Gilliam for Monty Python and 12 Monkeys.
For the common man, one could say = Self-induced peer pressure.
For critics = Awareness of times and self-induced necessity to keep with fads.
Obviously not all critics are familiar with this, but in a heavily "social-political" time all about empowerment, one has to accept that no matter which side of the spectrum is more powerful, BELIEFS are going to play an essential role even when the voters don't want to admit it.
This typically stems from a strong concern for what others in the field think. Add this to the idea that most people have difficulty forming "top 25's" and may pick movies they gave five stars that fit the general fad bill because "a five-star is a five-star," which I've heard from various people over the years via various topics, then the end of it is it's only "political bias" because "political bias" was "in" at the time.
I'd have completely accepted another female-directed film that feels less suspicious. Take a look through the MoFo Top 100 Films Directed By Women and tell me you don't find a few that might make a reasonable #1. In communities like this, Kathryn Bigelow is an all-too familiar name, and Sofia Coppola just may get either The Virgin Suicides or Lost in Translation to be ahead of all her father's films at some point. So much less suspicious than a three-hour slow cinema movie where the point is to explore the literal boredom of life by filming that boredom. On our own list, Jeanne Dielman didn't even break top 50.
As far as personal opinion goes, I'm going to say that I understood and at least appreciated the point and technique of the film, but not only do I think exploring boredom via everyday action too easily recreates that idea to enjoy even critically, but the movie that cemented all the essentials of slow cinema filmmaking is Satantango, so I compare every slow cinema movie I watch to that one movie. In the end, I gave JD a 68/100. As far as female directors go, my current favorite is Agnes Varda. I've given two of her movies 100's, as well as two other five stars (minimum 95). I also greatly appreciate Kathryn Bigelow, although I haven't given her any 100's.