Windshriek Reinforced Greaves doesn't apply 60% area buff to curse skills

It seems that "60% increased area of effect of curse skills" doesn't work, regardless where the curse gems are socketed or if the socketed gems are being used in tandem with blasphemy or not.

It doesn't show in the tooltips (it's not combined with other buffs to the area of curse skills) and it doesn't feel like it works in the game, either

From my understanding - it should be a global buff for all the curse skills of the player.