Okay, I got a picture of the house. I think the deck is at least 50% of the area of the house, and that house is likely 4500 sq.ft.
Note the (now typical) projection of the house far beyond the frontage of the neighbor. I think the enclosed wall area is around the same distance from the road. The city does try to make the frontages fit in, but because it is an "open deck" they likely allowed the projection forward. In the past, they did not allow for second floor decks that could be easily enclosed like this, without counting them as floor area.
The issue here, is the massive bulk of the roof over the upper deck. No roof and this would have been fine. Pergola roof with shade fabric or a clear rain cover would be fine.
Nothing close to the challenges of the monster home in your pictures (9 bedrooms with doors to the outside!)