You’re just seeing more of them because he’s more viable right now. The other fast flankers like Genji, Tracer and Sombra, does slow/chip damage, Doomfist’s ability to reposition and do massive damage in one hit allows him to break through armor.
My two top mains are Orisa and Sombra, so i can still deal with him, but a Doomfist that can properly combo can actually go through Orisa’s fortify. Fortunately, those players are still pretty rare in my games.