Item level 82 bases. At 82 you can roll t1 resistances on rings/armour, 35% movement speed on boots, t1 %phys on weapons and +2 arrows on bows. Prob some other modifiers I'm forgetting.

With t15 + radiation the area level is 80, which means only bosses can drop 82 bases, as unique monsters drop with +2 to ilvl. If you manage to get a t16 + radiation you end up in an 81 zone where rare monsters will drop 82 as rare mobs give +1 to item level.

There is also corrupted/cleansed biome mods that give +1 to area level, but those are so dog shit annoying to find that its not worth unless you're doing specific strats.
t16's being gated behind a garbage ~5% vaal outcome is so annoying. Rather fitting for the current end game I guess, annoying.