Re: no one has been able to invent new pronouns that sound natural as drop-in replacements
In German you have to know the gender of the Prime Minister, because the German word for a female Prime Minister is different from a male one. There is no gender neutral version, the same goes for most job descriptions, professions etc.
But they did clean up their act a bit in the 90s, Verniedlichungen (belittlements) were dropped, you only have Mann and Frau today, Fraulein is no longer acceptable, for example. Although they are still used in certain circumstances, such as parents reprimanding their daughter or son (Sohnemann - Junior).
But AFAIK there are few or no gender neutral terms, other than "it".