There is zero security if you dismiss every such measure to accomplish a level of security by saying that its just 'random crypto' that doesn't accomplish anything (why do you say that?)
>Nothing stops someone from registering your domain. Nothing stops someone from doing a Sybil attack and just always returning an attacker's account public key.
I think there may be some confusion in your understanding of the system. Registered names aren't visible, only their hashes. The design masks names through a verifiable delay function which forces registering parties to do lengthy computations to construct the lookup function. Since computations can be stored in bulk - names can be registered atomically across IRC servers without revealing what they are directly.
>Nothing stops someone from doing a Sybil attack and just always returning an attacker's account public key.
In the context of networking 'sybils' refer to being able to create multiple identities, machines, or so on controlled by the same person. But your usage of the term here is confusing because (1) users don't control third-party servers (2) users can't see names directly (3) there is a cost to creating names (4) and a threshold system is used to do consensus over name lookups and registrations (which was designed to solve the problem you're talking about.)
>The author would be benefit greatly by taking another look at blockchains for this problem. They typically are much better thought out distributed systems than what the author was able to come up with.
I would love to use a blockchain for this. There's only one problem. Currently there are no such blockchains that have zero transaction fees to use them. I think that such a system would be very useful. But it seems that no one wants to do it -- and working at blockchain startups for more than a decade has taught me that bolting forced monetization and funky tokens onto everything can make a system worse (or even unusable) for its intended purpose.
I think if you re-read the post you will see how I've addressed the problems you raised.