The more difficult something is to make the less competition you're likely to have and the more someone will be willing to pay for it. Sales might be slow now due to the lull in-between raid tiers but a slow sale is still a sale, and profit margins can be increased by gathering the items yourself or buying the mats when they're low. I'm not saying there isn't an issue with the effort vs reward, but the easier something is to make the more competition there's going to be and the smaller your profit margin becomes.