McCree can 1 shot her in the head. He also has an ability that can stop players from moving for 0.7 seconds. On top of that, with the recent changes to Sombra, she’s actually a viable counter to Tracer. Her time to hack people has been decreased and now it’s easier for Sombra to pull off a hack on Tracer, making her an easy target at 150 HP with no abilities to escape with.