Nothing there show you to be correct. You are arguing semantics from the wrong point of view. Voltage doesn't melt things, power does. Now go away and actually real about Ohms law rather than picking random things on the internet.
UHVDC uses extremely high Voltage to keep the Amps low enough to transmit over long distances using reasonable sized wires. It's exactly the same problem as USB PD solves by raising the Voltage on the wire. If USB PD kept the 5V of standard USB but tried to deliver 100W it would need 4mm2 cores for a 1m cable. It doesn't need 4mm2 cores because they raise the voltage to 20V to deliver 100W at 5A using the same cable. 240W USB PD goes to 48V and again stays at 5A to keep the cable core size identical.
I think SimonX is saying the power expended in the cable is what actually melts stuff (this would seem to be factually accurate), whilst you are saying the power of the load attached to the cable is not directly relevant to the melting because by changing the voltage you can deliver that power to the appliance without expending the same power in the wire (which is also factually accurate).