A structured bag stands up when you put it down and stays open when you go into it, which is the whole argument for the Sydney: things stay where you left them. The Carlie gives that up and buys back a divided interior — a zip pocket and two slide pockets rather than one cavity — and it sits against the body instead of holding itself away from it. Buy the Sydney if the bag is set down and opened all day. Buy the Carlie if it is worn all day and opened twice.
Same leather, so this is not a quality question
Both are leather with a polyurethane trim and both come from the same house, so neither is the compromise version of the other. The choice is a use, not a tier — which is why the ratings sit a tenth apart and neither number should decide it.
What structure costs
A structured bag is heavier before anything goes in it, and it keeps its footprint whether it is full or not. That is the price of standing up, and it is worth naming before it arrives.