That principle was inevitably going to be broken, and it doesnt surprise me that it happened so quickly
Despite being such a permanent-heavy deck, we have some great board wipes thanks to the reprint of Massacre Wurm and the new battle Invasion of Fiora

Alpine Grizzly Ashcoat Bear Ayula, Queen Among Bears Balduvian Bears Bear Cub Bosco, Just a Bear Copper Host Crusher Diregraf Scavenger Doc Aurlock, Grizzled Genius Dragon-Scarred Bear Drover Grizzly Druid's Familiar Duskana, the Rage Mother Evercoat Ursine Exuberant Wolfbear Fiendish Panda Forest Bear Friendly Teddy Golden Bear Goreclaw, Terror of Qal Sisma Grizzly Bears Grizzly Ghoul Hei Bai, Forest Guardian Hei Bai, Spirit of Balance Hurska Sweet-Tooth Koala-Sheep Kudo, King Among Bears Lumra, Bellow of the Woods Mother Bear Owlbear Owlbear Cub Pale Bears Phantasmal Bear Platypus-Bear Professor of Zoomancy Rampaging Yao Guai Razorclaw Bear River Bear Runeclaw Bear Ruxa, Patient Professor Spectral Bears Spirit of the Aldergard Striped Bears Studious First-Year Surrak and Goreclaw Ulvenwald Bear Ursine Fylgja Ursine Monstrosity Vastlands Scavenger Vivien's Grizzly Werebear Wilson, Refined Grizzly

Dropping a Turn 3 Thraben Doomsayer means you can make two tokens a turn for a single white mana