> If all you want to do is to watch YouTube and check out Instagram, and Google and Facebook have servers in a rack "nearby" (in the network sense) ala what Netflix does, then you don't need a globally unique IP to talk to them.
A "consume only" internet sounds like a second rate dystopia, doesn't it? (Where does the next YouTube/Instagram/Google/Facebook come from when the hurdle is they need to install lots of middle boxes to small, more siloed networks?) Not to mention the name "internet" itself comes from the global joining of a lot of individual networks. A re-balkanized "internet" with a lot of mostly disparate networks that don't really talk directly to one another hardly deserves the name "internet" at that point. (From that perspective CGNAT is an attempt to murder the internet from the inside.)
> the lower 64bits of the 128bit addresses doesn't count (due to privacy)
That's not how that works? For privacy a device is picking a 64-bit random number, sure, but that's still 64-bits of random numbers for a lot of devices to roll before collisions. It's not like it is just one device per lower 64-bits of address space. (Sure, maybe for "privacy" to avoid easy/obvious port scanning you superstitiously avoid "unlucky numbers" like ::1 or ::ffff:ffff:ffff:ffff, but that's still a lot more random numbers to roll than anything "the lower 64bits doesn't count" implies.)
(ETA: And of course, that assumes you are using privacy-focused SLAAC. There's still the power to micromanage a prefix with DHCPv6 and allocate every single one of those lower 64-bits if you really must.)
> For privacy a device is picking a 64-bit random number, sure, but that's still 64-bits of random numbers for a lot of devices to roll before collisions.
I don't have billions of devices in my home network, yet they eat 2^64 worth of addresses cause my ISP hands me a /64.
Which is fine. There are 330 million /64s available... per person on the planet. Your home network using one single /64 out of that isn't even a blip.
(Actually, if that's all you can get then it's not fine. Your ISP should be handing you, perhaps not by default but certainly on request, at least a /56 so you can have multiple networks.)
A "consume only" internet sounds like a second rate dystopia, doesn't it? (Where does the next YouTube/Instagram/Google/Facebook come from when the hurdle is they need to install lots of middle boxes to small, more siloed networks?) Not to mention the name "internet" itself comes from the global joining of a lot of individual networks. A re-balkanized "internet" with a lot of mostly disparate networks that don't really talk directly to one another hardly deserves the name "internet" at that point. (From that perspective CGNAT is an attempt to murder the internet from the inside.)
> the lower 64bits of the 128bit addresses doesn't count (due to privacy)
That's not how that works? For privacy a device is picking a 64-bit random number, sure, but that's still 64-bits of random numbers for a lot of devices to roll before collisions. It's not like it is just one device per lower 64-bits of address space. (Sure, maybe for "privacy" to avoid easy/obvious port scanning you superstitiously avoid "unlucky numbers" like ::1 or ::ffff:ffff:ffff:ffff, but that's still a lot more random numbers to roll than anything "the lower 64bits doesn't count" implies.)
(ETA: And of course, that assumes you are using privacy-focused SLAAC. There's still the power to micromanage a prefix with DHCPv6 and allocate every single one of those lower 64-bits if you really must.)