That's the flag of Austria-Hungary in the First World War. It is associated with the defeat in that war.
Austria-Hungary that might emerge in 1930s is a New Beginning for Austrians and Hungarians, and that black&yellow bicolor is supposed to symbolize a New Hope for them
That's the flag of Austria-Hungary since 1867 (since the Ausgleich) and it can't symbolize loss in WWI.