> I think the opportunity was 8+ years ago when every FW tool decided to do IPv6 with a different command line interface

well -- I had a look through them again -- in probably 90% of the cases cmdline interface is 100% the same (especially if ipv4banprefix comes into play)  and what differs is only the actual command (e.g. iptables vs ip6tables).  so Sorry, I haven't been convinced yet to live with it ;)