I remember when the A380 was starting to get some public media attention and there were these great sounding potential-perks of these new super jumbos: an on-board gym! a library! a creche! perhaps even an on-board casino!
In hindsight it was perhaps inevitable that all that extra space would just mean more people packed in just as tight as they are on smaller planes.
While I am sure its very nice up in first class, my A380 experience has been as soul-destroying and uncomfortable as any other plane.
This is probably going to sound like the pinnacle of first world problems, but: it's overrated. The main differences between business and first were getting actual bedding and having more attendants per passenger. And three types of champagne, because obviously just one isn't enough. The food was slightly better than in business but nothing outstanding.
There's a huge step up from economy to business since you get the lie-flat seats you can actually sleep comfortably in and good food/alcohol. Beyond that, you're mainly paying for exclusivity and status.
The 747 can be OK but not if it's a decades old one in need of renovation/retirement. Lufthansa had a few really old ones operating between Frankfurt and Boston until quite recently. The difference with the A330 I had on the same route. But I'd take Lufthansa on a 747 over their partner United on pretty much anything. The last few times I made a point of booking such that I was on a Lufthansa operated plane both ways.
I'm guessing that the limiting factor for the airbus was that it needed specialized infrastructure at airports and that most smaller airports just never got around to bothering with that; thus limiting where you can fly with them. This was always a risk and probably became more of a burden when it became clear it wasn't selling well.
That's not true at all, the cabin noise in the A380 is so much quieter than in older planes. It's night and day.