A Diablo 4 player has run the numbers to determine that the best way to grind some of the game's best loot is to run either a pretty low-tier Nightmare Dungeon, or the absolute hardest ones in the game - and not to bother with anything else.
In a post on the game's subreddit, user fpsthirty said that once they "got bored of aimlessly grinding to lvl100," they decided to turn their efforts to something more useful: "to record the item power of each looted item with the subsequent grouping by level of Nightmare Dungeon." The aim was to determine whether there was a significant relationship between item power and dungeon level, and their findings may be sobering for hardcore grinders.
To gather their data, they spent 18 days running 400 dungeons (five of each tier between 21 and 100), collecting and recording 8,104 Ancestral items in total. They say regret set in around tier 30, but they were determined to see the idea through to its completion.
What follows is a wall of data that I've struggled to parse, but a handy TL;DR provides a good place to start. It suggests that anywhere between Tier 40 and Tier 90, all Ancestral gear drops with pretty much identical power - 70% of drops varied by just three points. That still rings pretty true from Tier 91-100 (though the gear is very slightly more powerful), but you'll also have higher odds of getting an Ancestral drop - around 60% more at Tier 100 than at Tier 40.
As summarised by another user, "you get more Ancestral rares in higher tiers, they're just not really much better per drop quality-wise. So if you want a chance to get an 820 weapon and don't care how good the chance is, you can just run [Tier] 40s." However, if you want to get as many Ancestrals as possible per run, you need to be running Tier 100s - you'll get more on average, and very few drops will be Sacred.
"Realistically, you want max chances per hour and Tier 100s slow most characters down a ton, so you're going to have to figure out what makes the most sense for your character," they reason. In this players' case, the optimal risk/reward is around level 65, where, according to this data, they'll get 25% more drops and also won't be hugely hindered by difficulty.
That'll differ for each player, but it suggests that simply running the hardest dungeon you can isn't the way to go - you'll get way more Ancestral drops per hour if you focus on speed, and you won't take the item quality hit you might expect. The goal is to find the golden ratio of clear time and drop rate, and this data set makes it much easier to pinpoint your ideal break point based on how strong your build is.
Regardless of how exactly it pans out for you, some Diablo 4 players are taking these findings as further evidence that the late-game loot-grind isn't worth it right now. The top comment reckons this is "confirmation of little reason to push NM dungeons higher than necessary." Another argues that "every NMD tier higher than the next should drop better items," and that tier 40 "shouldn't even be dropping items as powerful as NMD100. Maybe once in a blue moon."
It's safe to say that after a pretty solid launch, Diablo 4 hasn't had the most staying power. Recently, the devs addressed the disaster that was the Season 1 launch, suggesting that they "felt like we were doing the right things." Hopefully Diablo 4 Season 2, which launches next month with new bosses, also comes with at least one fix for one of the game's worst grinds. It might be a tricky road to full redemption, but at least it's a start.
Elsewhere, number crunchers have determined that Diablo 4's biggest Platinum bundles don't always save you money.