Agreed AD has the range offensively to allow him to work and the defensive range to cover for some of his mistakes. They also got some play-makers like Reke and Jrue to get him some easy baskets. He ain't gonna all of the sudden be like an allstar player but they could make him a contributor or at least a neutral player instead of a negative one.
It works because AD is definitely a PF, and Jahlil is a C that cannot play anything but C. That is the perfect team for him that needs offense from their C, and AD can cover his mistakes on defense like you said. The Sixers hold the cards in that deal, need to play hardball cause there isn't a single big on the FA market or in this draft that they can get that will be on Jah's level.
How do protected lottery picks work?
Picks 1-14 would be protected, so it the Pelicans don't make the playoffs and the pick is lottery protected that means the Sixers wouldn't be able to get it. The Sixers want the protection top 5 - 10, so that if the Pelicans miss the playoffs they can still get the pick from them if the Pelicans pick is 11-14.