Greta doesn't know Tate is fake, but Tate definitely knows Greta is. (Greta is also probably unaware of the inauthenticity of her own role, I digress).
There's a pantheon of potential trolling targets that make significantly more sense than Greta - but the "teenage environmentalist" girl was picked, and then she "owned" him with her "hot take" about his wee-wee. Lol. Oh and then Alpha Chad King Tate can't even give a proper comeback and then oh dum-dum Tate had his pizza boxes out oh Greta got the big bad man arrested.
Puh-leeze.
Seriously Ant, you can't see how contrived that is?