How exactly do air resets work in this game?

I saw the cammy hooligan air reset tech inthis article from the front page and it made me start thinking about how air resets work in this game.

When you get up from a regular KD in SFV, you have 2 frames of throw protection where you can’t be thrown (from what I hear). Is this the same with air resets? Also if you’re really forced into a standing state, why aren’t lows guaranteed after properly timed air resets? Can you block low, but just have a “standing sized” hurtbox, similar to how fuzzy guard mixups are allowed to work in sf4?