Amazing HKG held on to the number one spot for cargo.
Their cargo component (both O&D and transfer) is almost entirely international, the one segment of the industry that was doing great (and in some cases, better) throughout the pandemic.
And with only the flight crew (if at all) subject to the kooky quarantine requirements (as opposed to cabin crew in addition), freighters weren't as adversely affected.
Passenger kms might be a better indicator of revenue
Within a given market segment perhaps, but they're certainly not worldwide, for a variety of reasons.
For example, sure a JFK-LHR and a JFK-CDG might be similar in revenue; but pre-pandemic, it wasn't uncommon to see an LAX/SFO - PEK/PVG/CAN/etc flight for $500 or less, including tax, roundtrip; just due to the slew of secondary carriers flying tertiary Chinese routes, at costs way below typical market.
You could hop on a nonstop to the likes of Jinan, Kunming, Qindao, etc for half the price of a BOS-DUB or BOS-LHR, despite being twice the distance.