I'm not speaking for Cal. Exot. here, but my understanding of PU Cote toys in general is that they could be considered semi-porous, but only to an extent. It's just a very thin coating of Polyurethane over hard plastic to give it a velvety feel, which under a major magnifier could look very slightly textured (depending on the thickness of the coat that's applied), like sandpaper. Horrible comparison, I know, but it's the best way to explain it. If you cover your kitchen counter with fine grit sandpaper facing up, is the counter now porous? Not really, but there are still little unseen textures that could harbor bacteria if we didn't wash the toys well.
Again, Cal. Exot. may be doing things differently, but that's how another manufacturer explained it to us. Hope that helps