I honestly think the UR Proft's/FOMO deck would be dominating the format almost exactly as hard without Vivi. Winternight Stories and a few other tools really push that strategy over the edge.
Most of the time, you drop or partially drop Vivi in the mirror match anyway. Cut out Cauldron/Vivi and you end up with an even more consistent, though less explosive, list. Standard still would not be able to handle that, and it shows by how often the deck wins without ever having drawn Vivi.
Vivi isn't the only issue. It's a compounding of broken pushed designs all stacked together. FOMO, Proft's, Tersa, Quantum Rider, the deck is STACKED and still the best aggro deck in the format by far without Vivi.