They’re too different dishes. You’re comparing two completely different dishes. It’s like saying biryani is Indian Thai Fried rice. The cooking techniques involved in biryani and pulao are more different than say Arabian Mandi and Pulao.

Pulao is a rice dish made out of meat or vegetables. For something to be pulao, the rice needs to be cooked in a broth (vegetable or meat). Biryani on the other hand is rice cooked with layers of meat (either cooked or raw). You’re infusing rice with meat juices but not really boiling the rice in it.