No, it's really the same thing with just different (and more structured) prefix lengths. In IPv4 you usually block a single /32 address first, then a /24 block, etc. In IPv6 you start with a single /128 address, a single LAN is /64, an entire site is usually /56 (residential) or /48 (company), etc.
Note that for the sake of blocking internet clients, there's no point blocking a /128. Just start at /64. Blocking a /128 is basically useless because of SLAAC.
A /64 is the smallest network on which you can run SLAAC, so almost all VLANs should use this. /56 and /48 for end users is what RIRs are recommending, in reality the prefixes are longer, because ISPs and hosting providers wants you to pay like IPv6 space is some scarse resource.
