1 cup flour = 120 g
1.5 tsp baking powder = 6 g.
This is 5% which is at the upper limit of 3 - 5 % used in most self-raising. Not all countries have salt added.
Yogurt (acid) reacts with baking powder (base) for fizz. Double acting baking powder give second rise in heat of oven.
I'm not sure about Bakers percentages with this 2 ingredient dough. Theoretically it is around 160% hydrated which would be a very wet dough but it doesn't look to be too wet at all. Yogurt is around 80% water. 1 cup is 245 g so about 200 ml water. 1 cup of flour is only 120 g which is your 100% reference. Typically a pizza dough is only around 60% - 65% hydrated so I have no idea how 160+% isn't too wet to work with.
After having tried wet dough handling (aarrrggghhh!!!) you really have to appreciate the skill of people like this.
https://www.youtube.com/watch?v=OjXWVSbWBV4