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.

There are some pretty big protests happening right now: https://bsky.app/profile/chadbourn.bsky.social/post/3mbvphn4...

Because v6 IPs are cheap, expendable and routing it over encrypted tunnels does not look suspicious. Anyone can buy a block and with little help announce them from multiple locations including home, mobile, uni wifi, and route further from there.

It's much more difficult to block.

A lot of anti censorship organizations have trouble getting more IPv4 /24 for cost reasons or moving it around to different AS since they would go offline.

With IPv6, you can get IPv6 /40 from ARIN/RIPE no problem. You slice that up into /48 and just start bouncing it all over the place. When one /48 goes down, you move everything to another /48, switch providers if required and continue.

EDIT: They also tend to get multiple blocks as well for when ISP figures out to root /40.

(going with recent ipv6 discussion) they probably failed to make it work properly and decided that it's easier to block it