Pretty sure he's mirroring my point - almost everything in Hearthstone follows a CMC = P/T formula with a few minor +/-1 CMC variations here and there almost identical to MTG. Including Charge stuff - there's plenty of MTG analogs in the Charge critters.
It's drastically undercosted for the effect considering how much everything else adheres pretty close to MTG costing except for Charge stuff. Heck, most of the Wolf Rider analogs in MTG have drawbacks even.
Haste is balanced at that cost in MTG because of the fact that blocking and instants exist - remove blocking and instants from the equation and the mechanic should be costed much higher. Plus there's that entire theorem to good card game design - interactivity - if you remove the ability for people to have any response to something and literally all they can do is sit there and let something resolve with no ability to deflect or deal with the impact it's a bad mechanic.
The only way Charge can be interacted with at all is via Taunt which is entirely proactive, there is zero potential to be reactive.