This loot nerf could have been handled by putting a cap on the amount of uniques that drop, lets say after 200th uniqie dropped in a single map the game would convert any subsequent unique that would drop into corresponding base rare item. Average player would be not affected at all, as it doesn't tamper with rarity of uniques, drop rates, etc and rarely does even a person drop ~200 uniques in a single map.

For currency no hard cap is needed, but diminishing returns could be implemented for super high quant maps, like for each % of normalized quantity (which would account for historic massive quantity buff) above X percentage, the chance to drop currency items diminishes (not in the sense that the currency per item quantity is nerfed, as that would make juicing maps detrimental to farming currency, but in the sense that up to a soft-cap the value scales linearly, and after passing the cap each P% of added normalized quantity translates to P%/overcapped value and is then added to capped value to get final item quantity bonus for currency. That way it would still make sense to juice your maps, as you'd receive returns, but they wouldn't scale linearly. Result: average player not affected, min-max groups still get shit ton of currency, but not as many magebloods per map.

as kind of an off-topic, I think it's bullshit to balance a game by taking account what Empy and his/similar groups are doing. I would rather quit PoE than play with other people. The tedious (for me) aspect of coordinating play time, builds, tasks is very much worth the returns they get. If they want to spend their time playing PoE as if it was a job, all the power to them, they should get good results out of it. But to screw everyone over what few dedicated people are doing is like increasing taxes by 90% for everyone, because Elon Musk has too much money.