Right, I wasn't saying that giving end-users something smaller than a /64 should actually be done. Not only does it require more effort but also it breaks highe

Right, I wasn't saying that giving end-users something smaller than a /64 should actually be done. Not only does it require more effort but also it breaks higher-level things as you said. I was just saying that there's no technical breakage that would occur, especially not SLAAC or privacy addresses.