The standard "ball" bullet used by the Russian military, at least, in the 5.45x39mm is designed to easily tumble once it is inside the target. It is more of an effect of the bullet's construction and fine tuning of the rifling twist rate than the caliber itself. But it is still supposed to remain stable with the nose pointed forward when traveling to the target. Otherwise it becomes extremely inaccurate and loses its velocity very rapidly, which causes it to fall short.
The QBZ family of rifles, both the older bullpup Type 95 and its variants, and the newer Type 191, fire a 5.8 x 42mm round, not the AK 74 'poison bullet'.
While I am sure the PLA has tons of 47s, and 74s still in active use, their efforts to modernize have included introduction of and seemingly wide issuance of the QBZ 95 family since roughly the early 2000s, and more recently the Type 191.
Usually when they do publicity videos or images, they like to show off the QBZ family.
If I learned anything of authoritarian countries claiming to be communist, they would never manufacture a whole new line of weapons without extensive testing, and if it turned out to be shit, they would totally have the self-reflection not to keep issuing it but to fix it and retry with a new variant. Totally.
