Since epic obsoletes ircii, it should provide /usr/bin/irc for people who just upgrade the distribution without paying too much attention. Former ircii users will expect irc nic server to work out of the box.
But doing that means that people can't install ircii without removing epic first, which isn't ideal either.
I don't think anyone will want to do that, since they're pretty much the same thing (with epic having some extra features).
Except that people are stubborn and resistent to change. Why force the issue? (does remind me to put something in the release notes, though)