Honestly, if you just want to craft and harvest things, do you really want to do the story? I havent seen anyone thats solely a crafter or harvester. And you wouldnt send a botanist to the frontlines or out on an adventure unless they had A.) a bodygard or B.) they knew combat skills of their own.

So no, its not really necessary a crafter or harvester be able to go through the story missions.

Now should they get story content or a series of quest lines focusing on their abilities? Sure.