I don't share the enthusiasm for longhaul charter/private jets.
Anyway, there is hardly anymore F on regional, so that is not relevant.

I have taken a private jet on EU-East Coast US and that was the maximum range. I don't see any private jet business on 13h flights HKG-EU or HKG-America. It will need to make a stop.
If you start getting 4 or 5 pax on some shared agreement, the level of comfort will be well below CX F.
And hiring your own private luxurious jet for longhaul is only for a few super rich.