My guess is either Yoshi-P has seen your enthusiasm and has cruelly pulled Fishing at the last minute with a maniacal, evil laugh (he's already probably deleted all your fishing gear on your v1 character(s), too); or maybe Fishing just isn't ready due to complex interaction with in-game systems, and/or because SE read our feedback and/or Yoshi-P didn't find the current ARR system fun enough yet, and made them make it better.

Did you like Fishing in FFXI? Most boring thing ever. Push a button, fish caught. Push a button, fish caught. Until they changed it after NA launch, partially to combat RMT. And then later tweaked for the same reason. And then later changed a little more. And then...

Point being: introducing Fishing at phase 4 doesn't mean it's locked that way forever. Any more than PvP, housing, free company points, and other things that we won't see until Phase 4, launch or beyond.