IDK for sure, but might be harder to maintain, monitor, and block.
One characteristic of v4 is it's somewhat reasonable to do a straight forward block on a range of addresses to shut down access. This is still somewhat possible with v6, but harder as there's simply a much larger portion of ip addresses that can be all over the place. It's theoretically a lot easier for anyone that wants to bypass a simple filter to grab a new public IP address.
One characteristic of v4 is it's somewhat reasonable to do a straight forward block on a range of addresses to shut down access. This is still somewhat possible with v6, but harder as there's simply a much larger portion of ip addresses that can be all over the place. It's theoretically a lot easier for anyone that wants to bypass a simple filter to grab a new public IP address.