But what if they had just said "We believe our display was not sexist, and we won't be changing anything." Is that any better than "We acknowledge that you think our booth was sexist, and we support anti-sexism in tech, but our display was not sexist and we're not going to change anything" ?
The former at least seems honest, the latter condescending.
This is actually interesting. I think there's probably a huge opportunity to communicate with your customers in this case. There's got to be a way to engage while respectfully disagreeing.
If you're dealing with a number of people who aren't your customers and were never likely to be, then you have a different problem as the presumed customer relationship isn't there. In this scenario you're dealing with people who don't care about your product and wouldn't buy anyway but mostly want to see you knuckle under. Engaging them as customers is a fundamentally misguided decision.