Its neat, and strong, and a card I expect to see a good amount of play
While there aren't many good mutate cards in red outside of Everquill Phoenix, you get access to powerful removal and other cards like Fable of the Mirror-Breaker that are proven to be solid staples of multiple formats
The most likely reasons are if it's sacrificed, if it's legendary and another legendary permanent with the same name is controlled by the same player, if it's a planeswalker and another planeswalker with the same subtype is controlled by the same player, if it's a creature with toughness 0 or less, or if it's an Aura that's either unattached or attached to something illegal
However, these services also have their issues
This doesnt get around Commander Tax, unfortunately, but does reduce Sepharas cost by a lot
Easy 10$ parking and easy access via Metro Peel or McGill with STM