Taking the extreme approach I see. Replace 1 shipwright with 1% of the population being viable to play "the crafting game".
Example: 5 major clans all get together and decide to divy up the ports between them, they all max out the buy orders and horde the resources for themselves (to boost their crafters who are hunting the 1st rate white whale blueprint) other than a small drip feed that gets through to the public market.
Hemp, Oak and Iron all goes to 800 per unit (as we saw before people were aware European Traders existed).
Those 5 clans are fine, everyone else is at the mercy of their pricing and effectively banned from ship crafting as their cost for production is never going to be anywhere near the capability for a low sale price of those 5 clans. The huge profits the clans make only serve to further fuel their ability to buy up everything in a nice recurring growth cycle of cash.
A nice system for the people on the good end of it, a total waste of time for everyone outside the bubble. At the end of the day it is a game and they have to attempt to make it entertaining for as many people as possible, keeping some semblance of resource accessibility to prevent inflation runaway is a sensible measure until they bring in the personal resource creation which will promote market competition and undercutting to keep prices sensible.