[syntonym2]

In german most job titles can either be masculine or feminine, and the masculine case is chosen "by default". Most job advertisements clarify that persons of all gender are welcome to apply. As the job advertisement is in english, it doesn't really make sense here.

[dotancohen]

In most languages, the male gender form is used also as the unknown gender. Not the default gender, but the unknown or unspecified gender. The distinction being that when the male gender form is encountered, it could also be an unknown or unspecified gender.

For another nice bit of related trivia, in Arabic the female gender form is also the plural gender form.