The complaints are in reference to Mei's "Mei-rry" holiday skin which was introduced for the new Winter Wonderland event that is currently underway in Overwatch. Skins in Overwatch are classified as either Rare, Epic, or Legendary with increasing in-game currency costs based on the rarity of the skins. Specifically, the original poster asserts that "the majority of people" do not like the skin and feel it is not equal in value to other skins in the Legendary tier. Furthermore, the original poster states that he believes it will be some time before another Legendary skin is released for Mei.
Largely, the complaints in that particular thread (and elsewhere) seem to center around the fact that the Mei-rry skin itself isn't very visually distinct from her default skin and other skins from that tier. While some bits and baubles are added to give the Mei-rry skin a bit more of a holiday feel, it's closer to a recolor than it is a truly new skin for the character. Some other users have countered that the value is in the skin's change to Mei's Cryo-Freeze ability - rather than encasing herself in a block of ice, she instead encases herself in a snowman. Although many skins only change the outward appearance of characters, some skins also change their voice lines or abilities. For example, Mercy's Halloween skin changes the voice line "Heroes never die" to "My servants never die" in reference to her witch costume.
Overwatch Game Director Jeff Kaplan responded in the thread and quoted the original post. He stated that the classification system for skins are based on a "gut feeling" of what Blizzard feels is "cool". He conceded that he believes that Blizzard's judgment for the quality of this particular Winter Wonderland skin was not well received, but he qualified that by saying that "coolness" as a concept is subjective.
In closing, Mr. Kaplan stated that players can expect something "pretty awesome" for users concerned that Mei won't be getting another Legendary anytime soon.
What do you think of this particular Winter Wonderland skin? Do you feel that the Legendary classification for it is justified? What other skins or cosmetics do you feel are in the wrong classification? Let us know in the comments below!