I know you can just block inbound non-established connections, but it feels like an extra step and complexity. Not to mention, that I really don't understand how IPs are supposed to be provisioned to devices on IPv6. Is there like a 50-100 page book you can recommend "for dummies" on IPv6, that hopefully contains at least a tiny amount of how to configure a common router and/or linux host.
SLAAC is the only way that works across all IPV6 devices. In that mode, the router advertises the prefix and the device assigns its own address (prefix + its mac address).
DHCPv6 exists but is poorly supported. It sucks for people who like assigning IPs individually from an authoritative place (through static dhcp entries on the router). But people like us are "doing it wrong", you see? We must accept that in this brave new worlds an IP means nothing.
Again, I don't know any of IPv6 enough to use it really right or wrong.
So it seems like it helps ISPs and large networks router… but they never had problems with address space running out at the high levels and almost all likely need to support v4 anyhow.
I think it’s been long enough to be honest that ipv6 was a spectacular failure by complicating an already complicated system into something no one actually asked for.
No human said “hey, networking sucks. Please make it much harder at my level!!”.
Lte and 5G can be v6 only, usually they also have NAT64 and DNS64 so you can get everywhere, but the less stuff that needs v4, the smaller their nat boxes are.
like 1.1.1.1/192.168.45.4 ... for a router that understands IPv6, that's the direct route to the sub-network, otherwise it will have to use IPv4, and the subnet route is treated as NAT and otherwise isolated.
To me, that would make more sense... then internal IPv6 might be practically limited to 10. and 102.168. in the nearer term, but adoption would be MUCH simpler in practice, and distribution would mostly already be established, however unfairly, but can then be broken into single addresses and vNext adoption could be that much quicker as a result of piggybacking.