Blizzard likely intends to address Mercy again in the coming months (After they finish all of the other stuff they are working on since they don’t multitask very well). So it would make sense to compile feedback into one location for something you intend to work on in the future so you don’t lose track of it.
Forum Moderator Note: I’m closing this topic as well because it’s more about moderator actions than the game, Community, or Feedback. Tom Powers posted the explanation for why we’re doing it specifically for Mercy in his first post in the megathread however.