But "if men are 3x as likely to interrupt women" is literally an example of sexism... the likelihood of interrupting a woman over interrupting a man.

Sexism IS a biological tendency. There is no rational basis for it when scientists are contributing to something as esoteric as string theory. This story overwhelmingly demonstrates how absurd sexism can get.

In any case it is perfectly acceptable to shame someone when they are being rude and excluding someone one from contributing. Especially when that someone is an expert.

The reason why I think she did not take any affront is because she already understands the subject matter. She's motivated not only in understanding herself, but in determining and helping others to comprehend. She can't actually engage in a proper discussion until she realizes that her counterpart also understands the material. When things get complicated, you have to continually establish a common basis for discussion which requires fostering patience.

not at all

sexism is behaviour

sexism is believing that women cannot do something because women are inferior by design, not thinking that they are generally weaker (biologically true) and it's probably best if it's the man who carries the heavier luggage

no. because men don't interrupt women 3x as likely but it's sexism to assume they do just because you believe it's true