>>16
Well, have you seen western forums without ability to register? I bet you haven't. This means that thos forums still attract shitstorms of children, trolls and people with no lives who actually have time to register and maintain an online identity.
Tripcodes weren't made to replace registration, they are just a way to keep your identity, but only when you need it.
There are a lot more good reasons for preferring 2ch-style boards.