The company has to pick one or the other. Swearing keeps out some, not swearing keeps out others. Why should either be more correct then the other? I see no problem with the company stating this unless you happen to be offended by developers cursing at their code on occasion.
I think even the most traditional programmer knows that swearing at code is A Thing That Happens. The question is not whether swearing at code is accepted at a company. The question is what kind of candidates they attract by putting it in their ads, and that seems to be putting things too far at one extreme.
Swearing at your code is one thing. Swearing audibly in the office.
Swearing in a job ad is - to my mind - somewhat unprofessional. It's not like this is an off-the-record conversation or casual chat - this is an official business document that has potential legal implications.
