Traditionally pizza dough should be made on the same day, but takes several time consuming stages and at least 3 hours to rise, so I suspect it’s just that the dough isn’t ready until later in the day.
A lot of the better-quality pizzerias now offer a 48-hour dough option. IIRC the longer it is left to rise, the less yeast it requires, and the easier it is to digest.
That is correct but traditional flour would not be strong enough for such leavening. Easy to digest pizza is a modern innovation.
Not an expert, but you should end up with more yeast in the end product for a long fermented dough. The yeast population will grow exponentially from whatever initial population was present. You should also end up with the sugars in the flour being more completely broken down into their byproducts (e.g. alcohol, co2).