> For instance, end-user ISPs are expected to give you a /64 or more instead of a single IPv6 address so that you don't need to NAT, but many of them don't

Name one? I've been on Comcast and Sonic, and both natively provide /64 networks. I've never heard of an ISP providing a /128.

> Meanwhile, IPv4 and IPv4 NAT works.

No, it doesn't. It breaks a million things more than it solves and it makes the Internet worse (and vastly more asymmetric, but that's repeating myself). NAT needs to die in a fire, and there is zero political or technical motivation to inflict its brokenness on a new protocol that absolutely does not need it. Evidence: that many ISPs are providing native, un-NATed IPv6 to their customers. Perhaps some don't, but someone will manage to screw up any given feature. They need to fix their shit, not coerce the rest of the Internet to break itself for their convenience.