You can't claim a loss on crypto if you lose the password or get hacked. Is declaring the crypto worthless different?
From the IRS memo[1] linked in your other comment, the fact that "Cryptocurrency B continued to be traded on at least one cryptocurrency exchange" is relevant to the conclusion that it still has a value. But unsellable NFTs are by definition not trading anywhere, right? So, ironically, the existence of a service like this might provide a price floor for all NFTs.