Earlier quoted context omitted.
Well, call me too sensitive then: it is sexist. If they need to explicitly mention that "women are welcome" in a footnote, that pretty much confirms that their choice of headline is saying that women are somewhat less than welcome. I don't see why being too sensitive is seen as somehow worse in the startup/developer community than being too insensitive. You'd think it would be smarter to err in the other direction...
Their choice of headline is a reference to a historical document from almost a century ago. Would it be better if we: a) rewrite history, or b) never reference it?
If it were me choosing the headline, and I had a desire to reference Shackleton's journey, what's wrong with "Wanted for hazardous journey: [...]"?