In the video you can see my inputs are always the exact same against the reset. The point of the throw is to defend against crossup/fake crossup/throw with the same input, that's why its an OS.
Towards the second sentence, that, I understand. I use parry airthrow fairly often as an air-to-air, but air-to-ground it's not as good because your options are more limited, you MUST reversal immediately, deciding what to do depending on whether you're still in the air or just landed on the ground.
That might work against that little reset, but not against like, well, most things. That throw would defend against Filia j.normal (parry) fall iadc airthrow, if you didn't land already, or tech Bella's Grab Bag if she ticked your parry into it. If you parried, you could take that ringing moment to confirm into something nearly gauranteed to hit and confirm with, with LP or Down.LP instead of "maybe airthrowing", which would be more punishable by super than LP anyways. It works in air-to-ground parry reversal, whether you're still in the air, or, just then restanded on the ground. Down/c.LP is a reversal meant to hit for low profiles such as Fortune, Painwheel, and Robo Fortune, so whether or not you're on the ground or above them at the moment, it'll hit. They are low enough to dodge parry s.lp if they land.
And if you whiff airthrow into the ground in a reset that leaves you not able to scoop up anything with that, that'd be extra recovery and grounds for eating a counterhit, if they pick and choose their resets such that. You don't want to risk eating a low or throw, either, and you can't really expect to read that in a good situation. For that reset that is an option select you have to react to, cause it's restand low, restand throw, overhead throw or s.hp command grab. It's unsafe and doesn't work in every situation and is more potentially punishable.