Joseph,
As I think GAW was saying (I haven’t actually read every post), Daas Yehudis means dressing like a modest Jewish woman and not like the prutzim. Now, even today with the lower standards that exist in some communities, and even by the goyim, there is still a concept of dressing modestly. While what is considered modestly is less modest than in our communities, it is still adhering to the idea of Daas Yehudis.
The question is how far you can go theoretically. I don’t know.