Today isn't a good day for Delta. This announcement is actually the "good" news. According to this
https://news.delta.com/deltas-777-ai...-amid-covid-19
Delta will continue flying its fleet of long-haul next generation Airbus A350-900s, which burn 21% less fuel per seat than the 777s they will replace.
My bold. If the 777 is that much less efficient than the A350, how is Boeing still selling them? What am I missing here?