@Bolt: some appliances are *much* more efficient (e.g. bulbs), some are just more efficient than the previous, while still being not that great a use of energy (e.g. dryers, dehumidifiers). While we may have wacked some insulation on our homes, we are still decades away from the efficiency they have in Nordic states and will remain so because the solution in most cases is to knock down our lovely 100 year old homes and build again from scratch. Our cars are more efficient, but then also bigger and therefore less efficient. I remember an article in the last 5 years that pointed out that the fuel efficiency of a hybrid is about the same as an original 2CV (facts may be subject to memory).
Any while we have made this progress, we have not made much progress on food (because the solution is to go vegan, and even the vegetarians don't want to do that - or to put it in Clarkson terms "I won't give up meat for a whole day") and air transport.
So while we have made significant improvements in some aspects of our footprint, this is in no way a significant change to the majority of our footprint. So, I would say, no, it's not just that there are too many of us (but there may be too many of us to all live a 90s Western lifestyle (cue images of cowboys in the 90s)).