Technically there's also a chance that the A380 could never make a commerical flight....
Indeed. Several A380 frames have made test flights, which B787 and B2707 have not - but Bristol Brabazon also has, and Brabazon has never made a commercial flight. First test flight does not assure entry into service...
The 787 will be a great success when it is introduced, but if the whole program vanished off the face of the Earth, would any tears be shed? The vacuum would be filled. The market dictates what the airlines want, and the manufacturers supply what the airlines need.
The airlines, in 1960-s, seem to have wanted (needed?) planes which could cross the Atlantic in 3 hours with 300 passengers 7 abreast, at a reasonable price. Boeing tried to supply it - and failed. No one filled the vacuum. The vacuum is still there. Aerospatiale eventually came up with a plane that could cross the Atlantic in 4 hours with just 100 passengers at a huge price. No one else got even this far... Tupolev, IIRC, never had the range nor reliability to cross the pond.
How can it fail? It has original ideas.
Didnīt B2707 have any original ideas?