Wait isn’t Amethyst an Era 2 Gem, and is capable shapeshifting really well?
Well enough where she’s one the very few characters in media that can legitamently and unironically Sexually Identify as an Attack Helicopter  , cause she can transform into one

No.
Amethyst is one of the last Era 1 Gems.

Era 1 Gems are gems that were made before or during the "Diamons vs Rose" war.
Era 2 Gems are the gems that were made after the war was done with Pink's "death" and the Diamonds nucking the planet with their light.

Amethyst was planted during the war but only came out of her wall after the war was over. But she still is a Era 1 Gem.