It is plausible that location used to be a bathroom in a now missing building. I just don’t think TP would hold up like that at all. TP is generally designed to come apart over time, especially in the presence of water, to help it go through wastewater pipes and get processed when it reaches the wastewater plant at the end of the line.
So I think, even if the holder is genuinely part of the original building that was there, someone added to it with, what looks like, a TP roll… For art.