.45LC case life certainly CAN be shorter than .44 Mag case life, and there are legitimate reasons for that. First, SAAMI .45LC chamber dimensions are very generous, based as they are on the old BP dimensions from the late nineteenth century. Modern cases are minimum diameter to handle the small (.451 - .454") bullets of today. Combine these facts with high pressure loads and the extra working of the .45LC brass can result in shorter case life, regardless of what some with limited experience believe. If all you have is a FA revolver with minimum chambers, this won't happen. A sloppy Ruger cylinder and lots of hot loads with older WW cases can and will result in more case loss than is usual with the properly-dimensioned .44 Mag.
I have usually had to work harder to get my .45LCs to shoot than I have with the .44 Mags I've owned. Again, there are reasons for that, based on sloppy chambering dimensions. This issue is well known among those with a lot of .45LC experience. The .44 Mag has the right dimensions and always has, it is a modern cartridge. The .45LC is almost the oldest handgun cartridge, chamber dimensions were less well undestood in the 1870s, and they had different needs (like dealing with massive BP fouling and very soft cases). I have gotten outstanding accuracy out of most of my .45LCs, but it is easier to get there with a .44 Mag.
FWIW I am a huge fan of the .45LC and have been for over 30 years. I curerntly have six .45LC firearms and have had numerous others in the past. Load soft .45LC cases to near .44 Mag pressures in enough sloppy chambers and you can see short case life. Not opinion - fact.