Part of what killed the hype was their announcing OW2 years before it was ready, resulting in all focus going to that while OW1 was all but abandoned to minor patches and a couple event skins. Years went by without a new hero or map (that wasn't for death match). Papa Jeff leaving was the canary in the coal mine moment in retrospect given the sexual harassment lawsuit.
Valorant has RIOT backing them up, and they're using the same CS:GO format that everyone can enjoy without having any skill at all.
As for Overwatch, the game has grown increasily unplayeable due to poor character designs, like Sombra or Brigitte for example, and the increasing number of CCs (Crowd Control) mechanics make it feel like shit when playing.
I hope OW2 is good, but I really dislike the support changes they've made so far, making skilled heroes like Baptise unusuable and buffing braindead characters like Moira or Mercy.