Personally, I say yes, for the sake of materials. Mob drops from level 56 range are typically useful for 56ish gear across the board. Unless you want to spend the gil (which in theory you may be able to recoup if you craft enough to sell), you'll want to keep gatherers up with your crafters to get the supplies you need to craft, to be able to craft better gear to gather, to gather better materials to craft, etc.

To a certain extent, though, crafting and gathering is somewhat independent from everything post-50. They help each other out, but it doesn't really do much for combat classes. Especially now that leveling dungeons give you guaranteed drops for your job, it's plenty easy to gear up on dungeon gear alone. Even more so considering how far Augmented Ironworks can take you before you upgrade to Shire.

Summation: Craft and gather if you enjoy it. Depends on what you expect to get out of the process.