Low intensity aerobics burns more fat than high intensity one?

False.

If you read energy systems chapter than you understand where our body takes energy from. While aerobic energy mechanism can supply enough energy for low intensity aerobic training, at higher intensities anaerobic energy systems are also being used. Therefore, the percentage of food energy from fat is in opposite relation to workout intensity (higher training intensity leads to lower percentage of food energy from fat). This ex4plains the origin of this myth. But you should note that we’ve talked about percentage. Nominal values might have different relation (50% from 800 > 70% from 500). There are also other aspects: high intensity enables you to train cardiovascular and other systems (while low intensity don’t provide such training), the higher training was the more energy will be spend during the following resting days and so on.
Finally, why should you mind how much fat was burned? The relevant parameter should be how much calories we burned. Whether we burn fats, carbohydrates or proteins (it’s not advisable to make your body burn proteins) our body will know to balance it as needed.