Your personal experience is meaningless compared to statistics here.
Tier / Pickrate / Winrate
GM: 3.12% / 52.02% (fourth picked tank, bottom third in WR)
Master: 2.52% / 48.79% (least picked tank, 0.01% above Sombra in WR, 3rd from bottom)
Diamond: 2.64% / 51% (least picked tank, 5th from bottom in WR)
She’s barely in a fifth of games (mostly in bronze and silver) and she certainly isn’t “owning” anyone.