It seems Apex Legends' Winged Avenger has been a bit too strong in the competitive meta lately. Valkyrie has seen a pick rate of 99% during the Apex League Global Series (ALGS) Championship, and players think this indicates she's overpowered at the top level of competition.
Competitive balance is a struggle in every esport, as developers work to balance the strength of characters across skill levels, whether they be casual players to professional players. This level of Valkyrie ubiquity is clearly an outlier, though. For example, one of the only times a League of Legends champion approached this level of pick/ban was Kassadin back when his ban rate was a whopping 95%.
Not only is Valkyrie clearly overpowered at the top level, but a Reddit post by DankChickyNuggs also shows the top comps played through ALGS, with the top played comp having a pick rate over 40%. The reasoning behind those other characters' pick rates, though, could also have to do with their synergy with Valkyrie.
Comments on that post speculated that the reason for not nerfing her so far is to wait for the ALGS to wrap up before nerfing the character — developer John "JayBiebs" Larson previously stated Respawn Entertainment wanted to avoid major balance changes before the competition, and it could be that approach is continuing for its duration.