I honestly dont see much grievous wounds around this game

Blame the people who refuse to build something that applies Grievous Wounds, like Executioner's Calling, Mortal Reminder, or Morellonomicon.

Grievous wounds cuts all forms of healing by 50%. Whether it is a flat amount, a percentage, or even passive regeneration. If you are not seeing players trying to apply grievous wounds, then you are either in a game where: 1) all the champs do not have a significant form of healing within their kits, 2) no one is building multiple lifesteal items, or 3) no one really understands or knows the mechanics behind grievous wounds, so they whine about how Aatrox, Xin Zhao, Mundo, Soraka, Vladimir, etc. are all OP and should be nerfed.

Sure, the duration is not long, but when an ADC is autoattacking then the target will definitely feel the grievous wounds debuff.

Willfully ignorant & arrogantly stubborn people that refuse to acknowledge the concept of 'counter-build'.