If you use it to exile a threatening commander, your opponent will either be forced to wait it out, denying them access to the creature they built their entire deck around for three whole turns, or they put it in the command zone, in which case its Swords to Plowshares minus the life gain
Pikachu has two attacks it can use, Charge and Thunderbolt
Commander Legends will see partner commanders with a single mana colour appear for the first time, introducing 41 new monocolour partners to MTG
You'll make copies of it whenever you cast that sorcery or instant spell, so that's a lot of swings on your turn, but they'll die (exiled) EOT so there is no reason not to swing
It just spirals out of control, building a dominant board state with relatively little material
It's possible that Hour of Devastation prices are low because the set simply isn't that powerful for Standard and most cards from the set are unlikely to find homes in tier decks, since Energy and Vehicles are still dominating Standard, and Hour of Devastation doesn't interact particularly well with either mechanic