While the interviews themselves were professional, I got ghosted after my third interview which was even with the director of the Marketing department and after having been told that I am the preferred candidate, but they wanted to interview others before making me an offer. (Likely because my salary expectations were higher than theirs...) I didn't follow up because I got another offer in the meantime, but I find this very unprofessional.

"This company does not hire based on merit" is all I wanted to extend to potential future applicants. They do not consider the applicants demonstrated ability vs. their requirements. Even after they specifically ask for an extended cover letter they simply don't bother calling for an interview. Worst part is they claim to have "stronger" candidates while you are probably overqualified. I guess this is how German companies operate in Turkey. Stay clear.