English does have Gendered nouns that are derived from either German or French, both of which are gendered languages. English just has some usually simple rules for it's gender and usually reserves masculine and feminine for nouns that are capable of having a gender or are personified or otherwise sentient but without any gender (German does this too as the word for girl is neutral gendered, but when referring to a specific person by girl, they will often use "girl" with feminine articles and pronouns. Similarly a robot id neutral in English, but Lt. Commander Data, from Star Trek, is given male pronouns.).
Most job titles in English are generally male pronouns when in the generic (as this common brain teaser relies on this assumption: A boy and his father are in a car accident and are rushed to the emergency room. The doctor on duty sees boy and says, "I can't operate on this child, he's my son." How is this possible? The answer is the doctor is the boy's mother, but because the riddle never associates gender with the doctor, the listener is primed to think the doctor is a man, thus creating the problem of the boy's father being in the wreck but the boy is also the (assumed) male doctor's son, which is impossible).
Some professions might use a gendered term and in these cases the male version is used as a generic. For example, the person playing a male lead in a play is a lead actor and the person playing the female lead is a lead actress. All male characters in the play are called actors and all female players are called actresses, but collectively all people with roles in the play are refered to as actors. So if I was putting out a casting call for actors to perform the parts in Romeo and Juliette, how does someone who wants to play Juliette know if I'm casting that role or not? And keep in mind, the Bard's work always called his cast actors universally... because when he wrote them, women weren't allowed to be actors so the Juliette was played by a man. Thespians today might call female actors "actors" out of tradition of the play, not modern feminism. Shakespeare himself milked this situation for all it's worth in many of his plays, with the character of Portia from the comedy "The Merchant of Venice". Much of the humor of the climax of the play revolves around Portia (played by a man in drag) having to wear drag to pretend to be a lawyer... creating a hilarious scene where Portia's is effectivley a man, pretending to be a woman pretending to be a man (the character's drag costume were usually placed over the actor's drag costume, rather than letting the man just wear men's clothes for the scene). To this day, Portia is occasionally played by men (and usually extremely masculine men) even when the rest of the female roles are given to women, just to preserve the gag of the climax.
And remember, English is in the same language family as German, with the French side being a later addition. German and English tend to share terms, especially with the "commoner's English" as French influences were first introduced into the upper class (both in that it was brought in when England was under William the Conqueror (who was French, lest you want to jokingly say the name fooled you) and was the language of choice in early modern era for Diplomacy (here, French terms entered other languages. For examples the Tsars of Russia were expected to know French starting with Peter the Great. Empress (Tsarina) Catherine the Great had to learn Russian as she was German prior to her reign. She knew French though).
This leads to many German profession terms being common in English. For example, English uses Programmer for one who programs. But since English isn't as strict about Gender, the male terms were used and rarely feminized, thus creating a generic masculine. Lest you think this is unusual to our language, it's not as a lot of monarchy's do not have a term for a female ruler as the concept of a female ruler is more recent then the term and Queen doesn't always mean Ruler and may better translated to "Queen-consort" which exclusively is gendered to the Ruler's female spouse (Ruler's male spouse is not a King, but a prince consort). So the historical female Polish Monarch Jadiwag II is correctly King Jadiwag II even though she's not a man. Similarly Cleopatra of Egypt is the Pharaoh of Egypt, not the Pharess or Pharohess as the term does not exist (in this case Pharaoh was always neutrally the "Ruler of Egypt". Queen Neferti was also referred to as Pharaoh and while she famously wore a false beard, it was not to appear more masculine. The beard was part of the ceremonial garb of the Pharaoh, like the crown, and there are many male Pharaoh who wore false beards because they couldn't grow sufficient beards and wore false ones. It's just associated with Neferti because it was more obvious that it was fake, and by the time of Cleopatra, the False beard was long abandoned.).
Since it is law that German law requires noting a male or female can fill the role and the English language uses the male term as the generic term in almost all professions (and has no way of knowing as there are no article genders in english) the (m/f) will sufficiently indicate the job and is easier than feminizing a word that does not have an English feminine equivalent (i.e. Programmer is a profession that developed in a time where women were common in the work place (and the first person in the profession was Ada Lovelace, a woman!) it has no traditional feminine term so you can't do Programmer(ess) and no other way to indicate that women are welcome. It's probably just a "better safe than sorry" matter for the law, but continental Europe uses Civil Law (as opposed to Common Law Britain and any country who spawned from that empire). Civil Law does not allow for case law and thus does not use precedence to the level of Common Law (case law is the concept in Common Law that two identical cases must return the same verdict, so the first ruling in a jurisdiction will effectively make a law for all equal and lower courts. Several U.S. States don't have murder laws on their books because case law ruled murder illegal long before there was a United States (they still have laws on sentencing convicted murders). Since Civil Law doesn't use case law, and thus only uses laws created by legislation. Precedence may help your argument in a case, but it's ultimately not the law and thus not as binding as it is in Common Law.
So, in this case, one German judge might be swayed by the arguement that English is not as strongly gendered as German and most professions using the masculine gender can refer to both females and males practicing the profession and rule it's not a crime, but that doesn't change the ruling of another judge, who is reading a statute law that says you have to do this for all job ads, with no exception for gendered language in other languages. And as the actor issue I discussed points out, English does have professions that have seperate terms for males and females (another example is a Steward(ess) on a plane... though these days, it's now referred to as a "Flight Attendent", there are other proffesions that use Steward(esses). Or a waiter or waitress (here, generic as wait staff, though a German employer could easily make the mistake it's a waiter).