What made the comment sexist? Because they used the word “girly”? Sounds like you are trying to attack something which isn’t the root of their comment. The “rah-rah” session filled with “yeahs” is the issue. The OP is correct, this company is filled with sales professionals mostly comprised big 40+ year olds. Try to respect and know your audience. Talking to the Salesforce like you would a bunch of children isn’t appropriate.