Both aerodynamics and dry trust have a lot to do with super cruising. We could take aircraft with horrible trust to weight ratio for example like the Concorde or F-106 that were supercruising. We don't know for sure for J-20 but it's quite possible that it's able to achieve it if his aerodynamics are not to draggy.That's just called eyeballing the aerodynamics, which we can't do without reliably knowing the thrust rating or the aircraft's weight.
We have had rumours of course of those figures, but nothing I consider to be sufficiently concrete that would make me confident enough to argue to a neutral audience that "J-20 can supercruise with WS-10Cs".
The preceding discussion therefore was specifically about the veracity of the rumours we've had for those numbers in the past.
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