Whoever bought the name on the blockchain is the owner within that decentralized DNS registry. If you don't like it, you can buy that same domain name on a different decentralized DNS registry (e.g. on a different blockchain) and try to use your influence to promote your users to use that one instead.
I don't recall ever signing a contract with any government agreeing to all these trademark laws we have today. Why should they have precedence over the laws of decentralized blockchains which people have chosen out of their own free will?