Stop spreading misinformation.
> You still need a stateful server to assign IPv6 addresses for most use cases, through DHCPv6. SLAAC doesn't even give you a DNS server yet.
DNS now comes in Router Advertisement per RFC 8106. No need for DHCPv6 anymore.
> And even if it did, many ISPs assign too small address spaces for SLAAC, or your networks isn't so simple that you can just auto-negotiate some address.
Most residential ISPs allocate in /48, /52, /56, or /60. Even if they allocate
in the smallest /64, it's still perfectly fine for SLAAC for most home users utilizing a single subnet.