'owning it' doesn't mean your own domain. you are only leasing that domain name until you either no longer pay for it or the government in control feels you no longer deserve access to it.
While you hit on a genuine problem, there are far fewer legal barriers to Google, Facebook, Twitter or Microsoft terminating your account than for US ICE to seize your .com and .org; ICE needs a warrant for seizure and more to retain indefinitely. Further, you can always get a non U.S. domain, e.g. .ch (Swiss) as used by Wikileaks.
That's unless you live in a country where it's becoming commonplace to filter out DNS. I'm honestly hesitant to have my online identity be obliterated at a whim by some reckless government of mine (France); they won't seize my dotsomething, but they will legally be able to block it out of existence, nationwide, without even the order from a judge. In that case, there are actually more legal barriers to Google terminating my gmail account on my government behalf than being blacklisted.
That's a little sensationalist, don't you think? What are the chances "the government" takes away your domain name? It's happened to an incredibly small percentage of domain-owners, I would guess.
Most people agree that there is a balance between the rights of individuals to do what they want, and the rights of the government to stop them if society benefits. For example, almost everyone agrees that the police shouldn't have unlimited power to search anyone they want. But almost no one argues that they should have no power to search people - just that a balance needs to be struck.
Your just using ad populum here. That's not an argument. There is no benefit for anyone to be gained through domain seizures. It's just another gateway to censorship.
Besides, you got the part about rights of individuals wrong. The right to do what you want doesn't stop where the government thinks it should. It's where you start infringing on another individuals right to what he or she wants.
"There is no benefit for anyone to be gained through domain seizures. It's just another gateway to censorship."
See, that's where you lose me. If you take a moderate position, like "the benefits of keeping domains free outweigh the benefits of domain seizures", you might have a point.
But saying "there is no benefit for anyone" [emphasis mine] is clearly, demonstrably false. If a website contains instructions on making bombs, there is some benefit in taking it down. If a website contains lists of hitmen for hire, there is some benefit in taking it down. Even if the website only contains copyrighted material, there is some benefit to someone (the copyright holders) in taking it down.
You can stick to your "censorship is always always always evil" stance, but you'll likely find few people willing to seriously consider it.