I totally agree but there is a market for this proposition be it FR or AirAsiaX and doubtless many others. I could imagine a time in say 10 years where there are them and there are premium profitable carriers and there is everything else.
You could almost see BA downsizing to 787 from 747 with F, J and then Y+ as the economy option (by the way interesting that VS are taking this up to 64 seats) to command a sensible ticket price.

On the other hand longhaul fleet utilisation, stopover accomodations, allowances etc dont make a longhaul LCC model a guaranteed success unless the fares are comparable to the likes of Air TRAnsat, Zoom etc