Cards that made me say "Wait, that's a rare?". I guess the Menace does push it up, but it's got a big crew number and a somewhat questionable etb (is vehicle spam really going to be viable). It really just feels like the set's Flametongue Kavu, which is normally a solid uncommon sort of thing.

Brazen Borrower has a similar questionable rarity so maybe they had a similar concern as far as limited impact?

So by itself it is a 4 mana to deal 2 damage to a Creature or Planeswalker. As a vehicle it is naturally resistant to creature removal with sorcery timing, and being a 5/5 with Menace means it'll probably win trades with chump tokens and trade evenly with more useful creatures.

Maybe the weak burn is there to prevent the new Tamiyo from feeling bad when Compleated? I dont know what planeswalker burn they spoiled tbh.