It's not about the case! The case has two functions, to hold the other components in place ( powder, bullet and primer) and to provide a seal with the barrel's chamber walls to prevent gas blow back upon ignition. The cartridge case walls near instantaneously expand outwards applying thousands of pounds per square inch against the chamber walls for a gas tight seal - there is little strength in the brass, almost all the strength to withstand that pressure is provided by the chamber's steel walls and the mechanical lock up mechanism which holds the breach face in position to prevent it from being pushed back allowing the cartridge case to "blow out".
This chamber pressure can be so great, it can cause the brass to flow, as often happens in rifle cartridges, making the case longer. It also increase the diameter of the case as it stretches to conform with the chamber surface. The breech face (headspace) limits the case's rear movement - the only area of the case that needs to be truly strong is the transition area that is unsupported between the base and the case wall. After ignition and bullet departure, pressure drops and the brass elasticity allows to "shrink back" a little towards it's original size, and in doing so, this allows extraction from the chamber.
Consider the case on a lowly .22 short rimfire would be blown to smithereens if it were not supported by the chamber and breech face. It's about what the original gun/s that were built for the cartridge were designed and proofed for.
In the case of the .44 Special you mentioned, that was originally a low pressure (by today's standards) early smokeless powder cartridge based on the 44 Russian black powder cartridge, lengthed a little. Even then, performance was not better than the black powder cartridge it was based on.
Often, as in the case of the .45 ACP, it's probably more about metallurgy, as the underlying design is the same. SAMMI for the .45 is 21,000 psi, yet the similar 1911 made for the 10mm, is at 37,500. Gun appearance similar, pressure near double. I would not be brave enough to load up a 45 cartridge to 10mm specs and shoot it in a WWI era Colt.
Smokeless powder, metallurgy, and in many cases gun design has improved to safely withstand still higher pressures.
44 Special, 15,500 psi
454 Casull, 65,000 psi . . . More than 4 times the pressure! I only shot my son's Ruger SA 454 once - good enough. I was hanging onto that gun like I was one grip away from certain death rock climbing - - and it still managed to come back and smack my middle finger hard enough to where i just handed that sucker back to him.