Airbus completely missed the reason why the 747 was so popular - particularly the 747-400. If you wanted the range of a 747, you needed a 747 - there simply were no viable alternatives until roughly 25 years ago.
Now, the longest range commercial aircraft are all twins, so you don't need to fill up an A380 (or even a 747) to make it viable.
Airbus was also fooled into thinking the 747 was a huge cash cow for Boeing. Yes, Boeing made money on the 747, but no where near the numbers Airbus believed...