Noone here is claiming that the new protocol would be compatible with IPv4 and I'd rather you don't beat a strawman. But there's still a gradient on how much t

Noone here is claiming that the new protocol would be compatible with IPv4 and I'd rather you don't beat a strawman. But there's still a gradient on how much the new protocol actually differs from the old in how networks are structured and how much work router, switch and client firmware needs to support it. The fact that I haven't seen a single non-buggy router firmware (and I've deployed quite a few IPv6 networks) tells by itself just how overbloated the standard is.