The plastic coating is another story, plastic is a known pollutant which leaks chemicals and doesn't break down.. Maybe, just maybe, that would be banned and not the leads?
I'm no expert and might be wrong that it even is plastic in Korda lead coatings (Argon? Something like that, whatever that is)!, besides their new coating seems more like a paint job of some kind, anyway I wouldn't care less about coatings personally and would be happy using bare lead
Maybe leads are totally safe in water, I dunno, it is of course used in roofing so it must then be (pretty much) safe in air as well, weathering over decades..
Lead oxide is formed by, basically, very high temperature treatment, so I'm not sure it is possible in nature, might be wrong, that stuff is, as I have spoken about elsewhere, PB02 is
REALLY, REALLY, REALLY, REALLY NOT something you want lying around unprotected anywhere even remotely near you!!!!!!!!!!!!!!!