Not particularly when you consider the basic 32-bit application limit is 2GB of usable RAM. Attempt to use more and the program will stop working.
With proper flags set, you can extend that to 3GB on a 32-bit system and 4gb on a 64-bit system. But far from all games have that set, and most that do, don't explicitly require it. (But rather its set for the convenience of modders and such and to simply prevent unforseen failures)