> there's also has proxy to mask the real IP

This is not going to make sense if it's using proxy by default.

> The bt system also work without dns

Technically yes. But it still need other services that did need DNS to work. I am mostly referring to the tracker.

Still you need tracker to tell you a list of peers.

> Clients and relays can exchange a encrypt key with private key. This action is just like How TLS work.

As of current NIP04 or NIP44 implementation, It's deencrypting speed is still considered slow and was not even designed for this actual purpose.