Sure, but that's the same argument I'm making: the unit of blocking will be the largest unit that is routinely allocated to a single user. In IPv4 space that's a /32, so people block by /32. In IPv6 space that's a /48, so people block by /48. Check out Let's Encrypt's rate limit policy, for example.
The difference I'm pointing out between IPv4 and IPv6 is that nobody is giving single IPv4 users /24s for their own use. But IPv6 /48s (which are theoretically somewhat equivalent to IPv4 /24s) are freely available. This is a problem because it makes over-blocking even more likely than it already is. And as you point out elsewhere, over-blocking is already an issue in IPv4 space.
The difference I'm pointing out between IPv4 and IPv6 is that nobody is giving single IPv4 users /24s for their own use. But IPv6 /48s (which are theoretically somewhat equivalent to IPv4 /24s) are freely available. This is a problem because it makes over-blocking even more likely than it already is. And as you point out elsewhere, over-blocking is already an issue in IPv4 space.