Adoption has increased, and will continue to increase, as there is more and more of a need for it to.

Honestly not sure why my comment is being downvoted. IPv6 became a standard in 1998. If it had been backwards compatible, it would have been adopted in just a few years.

Instead, here we are 26 years later, and the adoption rate looks like this: https://stats.labs.apnic.net/ipv6

That says everything about IPv6 that needs to be said.

Because you're saying things like

> Because it was incredibly stupid not to make IPv6 backwards compatible.

Without providing a non-stupid solution to a problem not solved for decades, and likely not solvable. (Also I assume you meant ipv4 forward compatible, you can name ipv4 hosts on ipv6)

Because it gets repeated on every thread on IPv6. IPv6 is perfectly backwards-compatible with IPv4 (you can run an IPv6-only host and still access hosts from the IPv4-internet). The issue however is that IPv4 is not forwards compatible. IPv4-only hosts cannot initiate communication with next gen protocol only hosts by design.

IPv6 adoption is a monotonously increasing curve (ignoring daily fluctuations): https://www.google.com/intl/en/ipv6/statistics.html

It's only a question of time.

Thread and Matter are IPv6 only. (They don't need externally routable IPv6, though.)

It's not incredibly stupid, because making it backwards compatible is impossible. How could IPv4 devices ever use IPv6 addresses? They simply don't have enough space to store the bits in the address.

Yep, you can't make a 32 bit number contain the same amount of information as a 128 but number. You have to use NAT64 to have the two things talk to each other.

> Too many IoT devices don't support it.

Huh? My thermostats are IPv6 only… (they're on Thread/Zigbee/whatever they call it now)

I mean, yeah, sure, there are old IPv4-only devices around. But we're now in a situation where a significant part is in fact IPv6-only. So,

> what a mess that would be

whatever mess that would be, we are already in it, and the way to fix it is forward.

> Sure, we could probably isolate them in their own little world, but - what a mess that would

No, it's IoT devices being on the public internet that is a mess. The "S" in IoT stands for Security.

> how it would soon take over the world. Didn't happen

It's at 45% on the public internet and growing. The majority of LAN connections are probably also IPv6 (mediated automatically through zeroconf without people even being aware)