In defensive terms, no, not really. They had to build it like this because these aren’t really walls per se, it’s just brick lining on the outside of an earthen mound, and mounds are, well, mound-shaped. https://gomadnomad.com/wp-content/uploads/2013/02/Bukharas-Ark-Palace.jpg
You’d think there’d be a reason beyond construction requirements, though—otherwise someone in the past 1,500 years would have replaced it with a more conventional wall.