The thing that had me puzzled was that the picture at Schoenbrunn looked as though it were out of doors, not even closed in, like a sheltered promenade or something. No way to judge its intended use. But the name would be appropriate for comfortable living spaces in what would otherwise be a fancy barn.
Imagine what an English castle must have been like in the winter. Heating by fireplaces only, which must have been of the fry your face and freeze you fanny type. And they just did not have the technology to prevent drafts. No wonder those canopied beds were essential.