Both 9mms and .45 ACPs live around here. Love the guns chambered for both.
Never really believed in the 9mm cartridge though. Weird because I love the .38 Special (if I can select the load used) and the two cartridges are really much the same. Haven't been sold on the notion that 9mm bullet design improvements truly close any perceived gaps between 9mm and everything else to which it is favorably compared. It's only the 9mm fan who stridently repeats that notion about the "great strides in 9mm bullet improvements." Nobody else in Forum-land ever seems to make mention of it. Guess no strides have been made to improve any other bullet diameter sold.
Do believe in the .45 ACP. It has "presence" with diameter and bullet weight to back it up. I still believe in bullet weight, even here in 2019.
Never really believed that the Krag cartridge failed to put down the Moro Juramentados, just as I never believed in all the Korean War tales of inadequate penetration of enemy winter clothing by the .30 Carbine. Sounds more like a lot of missing was going on or else only very poor hits.
Lots of stuff gets repeated, both in print and especially out here in Forum-land until it takes on a life of its own and becomes "gospel."