It's almost exactly just IPv4 with longer addresses. If IPv6 isn't a good design then IPv4 is even worse because of the address shortage.
No it's not. Slaac and NA make it a totally different beast.
If ipv6 only had dhcp6-pd, it would have been "just like ipv4 with longer addresses".
How many ways to be assigned an ipv6 address are there anyway? Two or three too many?
Why should the ISP know what devices I have behind their router?
Considering the amount of enterprise-ish thought that went into ipv6, they thought preciously little of privacy, for example.
The existence of privacy addresses suggests that some thought was put into this.
The prefix is also not delegated to that router, the router does npd proxying, and the ISP only routes the ips which have the corresponding NAs recorded into its database.
If your ISP runs the default router for your own LAN, they'll have full visibility into it on both v4 and v6. That's just how IP works.
Most ISP I have seen implement it like this. A large chunk of those "most" also require you to bind a phone number to each separate hwaddr appearing in the network via SMS. (Not all though.)
Those few that implement it differently, do the following:
They serve ULAs to the customers over slaac, and nat6 all the ULAs to a single ipv6 assigned to the router (actually a wifi hotspot).
I totally believe that where you live things are done differently, but this is exactly why ipv6 critics call it defective. It allows too large a variety in implementations.
But shitty or not, you have to somehow convince them, incentivise them to deploy ipv6.
Broadcast was renamed to "all nodes multicast". ARP was renamed to Neighbor Discovery.
Slight improvements: ND isn't broadcast, but multicast based on several bits of the IP address. This allows NICs to filter most of the irrelevant ones based on multicast MAC address. And subnet broadcast addresses were removed. There's only local broadcast to your own subnet and not to someone else's subnet, since IPv4 routers found that to be a bad idea and mostly started blocking it anyway.
Your cellphone company uses it - or would like to.
It's like SCTP: just because you don't use it doesn't mean there isn't a big group of people who do.