@PangPangSheMen Nah, it would be really hard to set up an RNG that functioned like that. They would have to be removing prizes from the prize pool.
It's simpler and easier for Respawn to just do it this way. The only way they could increase the odds of getting heirloom like you suggest would be to remove items from the loot pool once you've received them. But instead of doing that, they give you crafting mats. So the odds always stay the same. Basically they would have to lock those items on the RNG and force it to skip up or down one item until the player had unlocked everything. There are numerous reasons for not doing that though.
