I set up IPv6 at home and realized every single device in my house got a globally routable IP by default and was confused for a second.
Oh! This is how the Internet was supposed to be!
Remember, we only even bother with NAT bullshit in the first place because there aren't enough IPv4 addresses.
The difference between "has a routable IP" and "this should be routed" is exactly the problem for 99% of the population.
I'm not saying NAT is a good thing but at least it's one more thing from preventing network shares of everyone's pictures on shodan. I'm also not saying it's a good protection, but it's not zero.
Maybe if ipv6 had been the default since the beginning, then OSes and default configs would have been written in a better way.
I really don't see why we wouldn't end up in a world where home routers had a firewall by default and the user (or their agents) would open up ports as necessary.
Still like NAT, but better.