Pistol has its place but They don’t have the stopping power of a rifle if you’re wearing soft body armor pistols not going to penetrate it (in most cases)IDK, a pistol is far more handy in a close-in melee.
One of the reasons the US Army switched to the M4 is 14 1/2 inch barrel rifle is far more handy than a 20 inch barrel while Still maintaining the accuracy and range the army wanted
But for US civilians any rifle under 16 inch barrel requires a tax Stamp and falls into the NFA weapons so most guys just stick with 16 inches or longer the standard in the AR was 20 inch barrel