I can do it with a moral equivalent of a port forward. This situation was inevitable, but it's not like they just gave up and said "welp, guess they're separat

I can do it with a moral equivalent of a port forward. This situation was inevitable, but it's not like they just gave up and said "welp, guess they're separate then". We've developed basically every single method of communicating between v4 and v6 that are possible to develop. There's two address spaces, but they're linked into one Internet. (Or really, with NAT in the picture, it's millions of overlapping address spaces, but we still consider that to be one Internet.)