It's absolutely amazing that I can light my entire house for the same power draw as like one 100W lightbulb.

In terms of computing efficiency the big gain is that people use their smartphones drastically more than they do a personal computer at home, on average. And smartphones are hyper efficient compared to personal computers or laptops. An average use laptop will use ~30-60 times more energy than a once-daily charged smartphone across a year.

That also goes for people watching things on their smartphones instead of a 65" television.