Boeing proved "Big Plane" was profitable with the 747.

Unfortunately for Airbus, it also stopped being profitable before they finished the A380.

Probably not again given what a commercial failure it was

More of the same but bigger? While it is a feat of engineering to make an aircraft the size of an A380 it is essentially the same design as every other commercial airliner, not revolutionary.

Super impressive, but I agree with this, it was an easier project to plot on a spreadsheet and forecast a path to profitability.

Using current technology and looking back at the Concorde to make any predictions on supersonic passenger travel generates a spreadsheet with a lot of red on it.

If somebody wants to burn their time and money trying I am totally cool with it. If they succeed in their vision they will be handsomely rewarded and transport gets faster. If they fail they still tried to make the future more amazing.

Hell yea brother

Without A380 there would be no A350 XWB.

Why is that? (These are my favourite planes to fly on, curious how the A350 is derivative given the apparent difference in packaging.)

That's kind of a ridiculous statement. With the money spend on A380 they could have developed a whole lot of different things.