> Well, the generally-accepted term has been "salesman" for over a hundred years

Who cares? Did your ancestors coin the term or something? You can keep writing "salesman" whenever you write things yourself. "Salesperson" doesn't seem at all offensive, and I think it's bizarre to nitpick such a trivial and irrelevant aspect of the article. It reads to me like political virtue-signaling since the article has nothing to do with the gender of the traveling agent.