The only place I could see Crafted weapons being relevant (Read: Worth the effort) without making any current content obsolete would be as an i210 weapon, and only because you would have the option to overmeld them which would give them a *small* bump over now easily obtainable Eso weapons for anyone willing to spend the time/gil, but would likely be replaced by a Sephirot weapon before it even finishes bonding (Assuming the player does actually raid).

The only content I've ever seen be obsolete on release was the Bismark weapons. Personally I think that was an oversight on their part and one they're unlikely to make again.