I was taking a methodology course for my MA. The course was co-taught by different people. Whenever someone gave the lecture, they were also responsible for the seminar that week.
On the week that the head of department was scheduled to give the lecture, he showed up late. After arriving some 5-10 minutes late, barely apologetic, he gave a rush and confused stream-of-consciousness type lecture. It was clear he wasn’t prepared. He then, five minutes before the end of lecture, declared he had to leave. A busy man, with more important things to do. Clearly he was too important to do things like teach, or even keep track of what his job was. On his way out the door, he assured us that our seminar leaders would discuss the material more with us.
Except he was the seminar leader.
A junior female academic, this her first academic post, was in the room. It was her responsibility to convene the module. She didn’t say anything about it, didn’t call him out for ditching her with the work (he was her boss after all). But we all knew he’d just dumped the seminar on her, without even paying enough attention to know that it was his responsibility. She taught the seminar and straightened out his teaching mess.
Leaving women with the work is sexism, just like men thinking of themselves as too important to do this work is sexism.