You know, this is an interesting take on it, but it does seem a bit strange to me.
Namely, if Piglin’s are desperate for gold, so desperate they’ll do anything, then why does wearing gold make them passive towards you?
If anything, shouldn’t it be the opposite? They have no problem killing a player who isn’t wearing gold, but at long as you have a golden hat or golden boots, they’ll let you pass by unharmed (unless you break their other rules). If they were truly driven by nothing but greed for gold, then I would expect them to attack players wearing gold on sight to try to get it. But it’s the opposite.
Gold certainly wouldn’t let you blend in with them, they clearly recognize you as something other than them, and brutes still attack you regardless. So that can’t be it. Piglins are still smart enough to barter, to understand that things should be given in exchange for gold, and they understand the difference between gold ingots (currency) and gold items (gifts). They also can’t always be distracted by gold. If they’ve been hurt, then they ignore it in favor of attacking you.
So, what if gold isn’t so highly valued by Piglins purely because of it’s association with Netherite? Or maybe that’s where the idea came from initially, but over time as conditions worsened and stories were lost, gold came to have a new meaning for piglins: safety from infection.
Fun fact about gold irl, it has strong antimicrobial properties. Silver and a few other metals do too. Gold in minecraft also has significant healing properties, AND gold has significant anti-zombie properties. Golden Apples not only heal players, but they can be used to heal a zombie villager. Glistening Melons make health potions, and Enchanted Apples are one of the strongest healing items in the game.
So maybe the Piglin’s strong fondness for gold is less about Netherite, and more about a belief that it may offer protection from Zombification? If that were the case, then Piglins being more trusting of players wearing gold makes sense. It’d be the equivalent of feeling more safe around a person wearing a mask today. A player wearing gold has signified that they are protecting themselves and others from the infection.
This theory is further backed up by Piglin’s singular natural enemy (they hunt Hoglins, but that appears to be for food, and the babies get along), withers. Piglins are hostile not only towards the Wither itself, but towards Wither Skeletons. And it’s only Wither Skeletons. Regular Skeletons and even Zombie Piglins aren’t attacked by Piglins, but Wither Skeletons are on-sight. Why? Well, maybe they have something to do with this infection. Or at least, maybe Piglins believe withers have something to do with this infection.
It’s also worth noting, when you spawn the Wither, the achievement you get for it is “The Beginning?“ and for killing it you get “The Beginning.“ Which is an odd string of achievements for spawning in and killing an out of the way boss. A strange parallel to when you enter The End, and earn “The End? Or the beginning?”.
The constant implication is that you’re starting… something. Something bad happened here, and you may not have all the answers, but you do have two hands and you can try. You can start something new, or maybe bring back something old, and who knows? Maybe you’ll find the answers given enough time.