Appliances which use universal power supplies tend to be low power. The highest-power device with a universal PSU that I can think of that the "average" person

Appliances which use universal power supplies tend to be low power. The highest-power device with a universal PSU that I can think of that the "average" person would have would be a computer, but even high-end gaming computers tend to top out around 500 Watts when running full-bore. Even large TVs don't usually draw more than 100 Watts at most. The rest of the devices with universal power supplies tend to be things like phone chargers which draw almost no power. None of these devices draw enough energy for the increased efficiency to matter. Devices where it would matter tend to have large motors or heaters that run directly off line voltage.