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A while back I stumbled across a gaming community website about adapting a "monster parts" salvaging system into D+D. This is a trope we see a lot in MMO games like Warcraft, FFXI and their ilk, which meshes with their crafting subsystems. My initial reaction was "squee" but having let that concept simmer on the backburner of my brain a while now, I think it's actually kind of a dead end.
In MMOs, the goal is "keep players subscribed", i.e. engaged and invested. So there are built-in slow-burn crafting skill trees that develop alongside materials looted or mined from progressively harder/rarer monsters and locations. Farming, trading, and consuming materials to slowly "skill up" craft skills becomes a subgame alongside character fantasy-class leveling and the endless quest for better gear, to keep players engaged. Once the game has been running a while, these craft skills are mostly a time and currency sink until endgame levels.
But TTRPGs fundamentally don't work like that. The MMO activity of "farming" (mining, fishing, gardening) works because it's largely a solo time sink. The sense of accomplishment in trudging through the hoops to endgame-level craft skills oesn't map to TTRPG gameplay. Conceivably yes you could dedicate a portion of group session time to bookkeeping characters' use of downtime for crafting, but it would get very tedious very quickly to narrate one fish, ore nugget, mandrake root, or rusty orc dagger at a time.