Is that why last generation scores higher on benchmarks in comparison to Core M? Because Core M is better?
The only way to test the benchmarks for the Core M is with the Lenovo Yoga Pro 3, which provides only 3.5 watts of power for it, which significantly lowers any potential for the Core M to go above mediocre speeds. The new MBA would most likely (99%) provide it with at least the minimum 4.5 watts, but most likely around 6 watts as other posts have stated.