Hm care to share some proof of that as somehow I doubt it given all the ban evasion that is going on. And do you mean you literally can't register, or there is that evil fee thing if you try to create new account?
I think he is talking about evil points. Evil points get added to your IP address and similar ranges if you do some "evil". Remember that we had those cases in the Croatian section where it was reported that friends of our local community members couldn't register because their newly-created accounts got evil points assigned to them? That happened despite them never having used Bitcointalk before. That's also one of the reasons why we have some users who can now whitelist accounts that have been branded as evil.
I don't think IPs get banned here because many people use VPNs and TOR. It would just create more problems.