I a not a wing designer
but basically the trade
off is aspect ratio versus wingspan.
I would say that all things equal span is better than winglets, which as is pointed out are not necessarily a "lifting" feature.
My understanding is they could increase span (aspect ratio) on the 777, still fit in the gates and they handle the vortices on certain 777 with other tricks.
Ultimately it's payload vs. range. No tips? more fuel/payload.
Also maybe in context you have to think about when the 777 was designed. Maybe the aero guys just weren't there yet on tips. Everything after that was an evolution.
No doubt about it the 777 is a huge moneymaker for the airlines.
In regards the airport
infrastructure - There are still a lot of places that can't accommodate a 380 - infrastructure in the west moves a lot faster.
We now return to our normally scheduled sailing discussion...