MMO economies like this have several issues:

-Everyone is selling the same thing: NQ vs HQ and cost are the only things that differentiate products. Considering that NQ is universally viewed as vendor trash, cost is the only thing you have, which is why the market board is nothing but undercutting.

-Crafted Battle Gear is inferior to Token/Raid Gear: Crafted gear can be on par if and only if you HQ and dump a lot of gil into materia. The fact that the crafted gear requires token mats adds insult to injury because the amount of tokens you'd spend on it would probably be better spent just getting the token gear.

-Mats usually sell for more than the final product: Even if I made all the materials myself, I'd be better of selling the individual materials than the end product because total profit is higher and I a wider range of people will want the mats than the specific item I was going to make.

The real world economics argument doesn't hold in MMO economies. In the real world, everyone can't make equally good products. MMO economies don't really offer the flexibility to differentiate your product from another to offer real competition. The concept of HQ and NQ wasn't a bad idea, but the way it is handled has make NQ just another form of failing the synthesis and HQing being the new normal success.