The "reputation" concept has to be applied to network blocks in IPv6, because of privacy addresses, and they very clearly aren't doing that for whatever reason. I get at least one captcha a day from a stock Android phone that's been connecting from the same damn /64 for almost a whole year.
But there are way more /64s than /32s. They could apply it to /32s in ipv6, but then customers would share rep unless ISPs lease out /32s instead. Unfortunately gotta pay to play.
