There are some cars coming out next year that are more energy efficient than a Tesla, like the Hyundai Ioniq 6, but I don't know of any currently widely available vehicles that are.
By energy efficient do you mean kilowatt hours / kilometer (or equivalent units)? The standard range Model 3 – the most efficient one – is apparently 15/16 kWh per 100km, which is pretty much exactly the same as a VW ID3 (15.5 - 15.7 in Pro spec) and only a little less than a Hyundai Ioniq 5 (16.8).
Sitting on my hyundai kona ev. In 2833 kms, consumption was 13.5 kwh/100km
A tesla weighs 2-3 times more than a compact car, so that means it must be extremely efficient pound for pound. Nevertheless, I doubt many people, until recently, bought Tesla's because of (ostensible) environmental concerns.
Every single Tesla owner I know bought it for environmental reasons.
How does your efficiency argument follow from merely weight?
If you can move a heavy object using less energy than others move a much lighter object, then it would seem that you are quite efficient. Unless we're talking about constant speed in a vacuum.
Yes, but where does the less energy argument or data come from?