MwRYum
Major
I think we've found the key to why the shotgun is absent in PLA doctrine, throughout its history the PLA has fought organized, standing armies of other states, many of which at the time could be considered better equipped and more centralized than the PLA itself. Throughout the 20th century and into the 21st century, the shotgun has shined the most in urban combat, jungles, naval expeditions and general counter-insurgencies, where an organized army fights a scattered enemy, not in plains and fields or even hills and mountains but places where the opponent can 'disappear' and 'reappear'. The PLA has never really fought an extremely intense, organized guerilla opponent nor has the PLAN ever had to deal with mass boarding and close quarter ship to ship fighting. Even Russia which until recently never really used shotguns, began using the semi-automatic Saiga 12 in actual combat in Chechnya, a break-away from old Soviet era doctrine.
Or like what I've said previously, since in the past PLA used what they could capture from their foes, with none of them - the KMT troops, warlords' armies, and the Japanese - used shotguns, compounded with Soviet's doctrine that has no place for shotgun at all, that'd what explained why PLA don't incorporate shotguns into its arsenal, since they made by w/o shotguns and never operated in combat zones that'd be best suited with shotgun.
That said, they faced US in Korean War and the India in the border disputes but I don't see those has significant impact that'd make on PLA, not to mention the Soviet doctrine that still has imprint on the PLA.