The top ten are:
1 LHR
2 ORD
3 FRA
4 AMS
5 YYZ
6 LAX
7 ATL
8 SIN
9 CDG
10 CGK
Obviously LHR makes the most sense, but surprised by the omission of the Middle east Hubs, or even IST, since Turkish Airlines serves the most countries
Also if the list is about international connectivity, why are ORD and ATL on the list?, aren't they predominently US domestic routes?