I just dug out a pile of Playmobil rugs I have - and maybe I'm imaging it, but I think the rug that came with 5316 (Blue sofa set)
is smoother than the one's in the original Victorian sets. So maybe they did change the manufacturing process. Or maybe it's the age?
I also have a rug that's from a 'modern' house set (not sure which one) and I think that one is cardboard?
I need to wait until I get these sets to compare, next time they have a sale on