How is D.va balanced?

Doom wasn’t meta in beta two??? Hell even in beta one when he had his slow he wasn’t meta or hard meta he was just a solid pick for brawl not even dive (brawl was being played in owl).
Dva monkey and Zarya are all being played in owl and in the highest ranks, I literally see them in every gm game I’m in… people cycle through these three and barely pick anything outside of the top dogs, saying this is a knee jerk reaction is just dumb when the pros and top 1 percent are also abusing the same 3 characters.