You miss my point: the optimizations on ground experience for domestic first class can save you 20-30% of the time because the actual domestic flight time isn’t that long. On a transoceanic flight, to generate similar time-savings, you have to make the plane faster.

Comparing domestic first class to transoceanic supersonic is misleading.

To be entirely fair, that’s a single image, and, it’s a marketing website. Of course they’re going to show a luxurious seat. The truth is that the interior will probably look like Concorde: more spartan than luxury.