Man, that is it exactly, they threw everything and the kitchen sink into it AND made it unnecessarily difficult to update systems / be compatible with IPv4.
They should have had IPv6 with a header or config for IPv4 gateway(s) configured at the IPv6 boundary of your current network (could even be local / on device if needed). Want to talk to IPv6 - you go native. Want to talk to IPv4, connect using known prefix to IPv4 boundary gateway and it NATs you out.
The implementation / firewall changes needed for this are crazy, the config stuff also crazy, the number of layers of encryption I'm hitting (I'm IPv6 on a VPN using wireguard tunnels and browsing in SSL on my remote machine) seems nuts.