I assume it's a work-around to block people from simply creating nation-aligned alts and using those to get the goodies 3 times faster (or 6 with two alts etc).
If you want a roleplay reason, just assume those picks are fashioned specifically for the buyer, considering how usually you can't add hp or focus boosts on such tools. This is different from catalyzers or crystals, they have no extra qualities and are meant for any person's consumption.
Personally I'm at a loss as to why gen mats are not tradeable (except the argument in the first paragraph), so I support unlocking the trade of both mats and picks.
If you want a roleplay reason, just assume those picks are fashioned specifically for the buyer, considering how usually you can't add hp or focus boosts on such tools. This is different from catalyzers or crystals, they have no extra qualities and are meant for any person's consumption.
Personally I'm at a loss as to why gen mats are not tradeable (except the argument in the first paragraph), so I support unlocking the trade of both mats and picks.
---