Never engaged in "trench warfare" except in basic training, but I have crawled into a few foxholes with my 1911 pistol (made in 1917.) Since it was carried (by regulation) in a full flap holster and I always cleaned it BEFORE I ate those disgusting frozen canned rations, it collected less dirt than my handkerchief.
Since all of my 1911 pistols now have bull barrels, and I have fired a large number of rounds through them under all conditions, I have come to favor them above bushing guns. I would have no qualms about carrying one in combat.
I sincerely doubt that IPSC or other load em up and bang away shooters use bull barrels because they collect less garbage. I would lean on my own experience and say it is due to the heavier barrel's dampening muzzle flip and allowing rapid shooting without upward drift.
If you look into it deeply, you will find that the 1911 was almost never used in trench warfare. It was the weapon of choice for patrols crawling through no man's land. Read about it in McBride's "A Rifleman Went to War." But, be prepared for a shock concerning use of the 9X19 caliber in the Luger.
The match bushing was at its apex for NRA Bullseye. If you compare the number of shots fired in bullseye competition vs the action shooting sports, including practice for both, you will find that bushing guns are subject to much less hard use than bull barrel guns. Bushing failure was a fairly common occurrance (especially the prong bushings). How many bull barrels have you had to replace because of failure at the muzzle end?