RFC 6530 doesn't mention those character sets explicitly. It proposes allowing all Unicode characters, apart from some control characters.

It is true that the RFC recommends mailbox providers take normalization into account. A mailbox provider that allows i and dotless-i addresses to be routed to different mailboxes is careless, if not actually uncompliant. I don't know if any popular provider does this: I'm guessing the authors created their own to demonstrate this attack.