About the sexism: She didn't make a big fuss. She just coded a neat funny bot that only talks when triggered by a certain joke. She's highlighting how tiresome some jokes are when repeated too often.
She's not say "Toxic Environment because of constant sexist remarks"; she isn't calling for anyone to be disciplined or sacked. She's just talking to people.
Other people are saying the joke is sexist, I'm saying it's not. That's all.
As a fellow guy, let me tell you: it is much harder to see something when it benefits you than when it hurts you. You may never notice two steps up to enter a building -- unless you're in a wheelchair. So you should never assume that sexism doesn't exist just because you haven't noticed it yet.
They wouldn't stop using the bot when she asked them to because it made her uncomfortable. It's been pointed out in these comments that she could have sued this company into a hole in the ground with a chat log and that fact. I think "Judge will probably say it is" says it's sexist.
"It is argued that sexual objectification is a form of sexism" - http://psychology.wikia.com/wiki/Sexism