While it does require a fair few cards to execute, it could be the real deal
If we look at the odds of drawing into one or more Humans when Sigarda triggers, youd need around 22 Humans in the deck
1 Boreas Charger
Morph isn't just four copies of a specific Shift target, but four more copies of every Shift target, making it a lot easier to get those big threats out early, but also making these decks a lot more consistent, and a lot harder to deal with
Building your deck is very challenging and playing against a wide variety of different cards offers up its own set of challenges
Yes, current enfranchised players love Modern, and some even love Legacy and Vintage, but adding 25 years of cards to Arena , along with a bunch more events to support these cards, hugely increases the complexity for new and intermediate players, who mostly play Standard and Limited anyway